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500 °C is considered asphalt. Vacuum distillation separates it from the other components in crude oil (such as naphtha, gasoline and diesel). The resulting material is typically further treated to extract small but valuable amounts of lubricants and to adjust the properties of the material to suit applications. In a de-asphalting unit, the crude bitumen is treated with either propane or butane in a supercritical phase to extract the lighter molecules, which are then separated. Further processing is possible by "blowing" the product: namely reacting it with oxygen. This step makes the product harder and more viscous. Bitumen is typically stored and transported at temperatures around . Sometimes diesel oil or kerosene are mixed in before shipping to retain liquidity; upon delivery, these lighter materials are separated out of the mixture. This mixture is often called "bitumen feedstock", or BFS. Some dump trucks route the hot engine exhaust through pipes in the dump body to keep the material warm. The backs of tippers carrying asphalt, as well as some handling equipment, are also commonly sprayed with a releasing agent before filling to aid release. Diesel oil is no longer used as a release agent due to environmental concerns. Oil sands Naturally occurring crude bitumen impregnated in sedimentary rock is the prime feed stock for petroleum production from "oil sands", currently under development in Alberta, Canada. Canada has most of the world's supply of natural bitumen, covering 140,000 square kilometres (an area larger than England), giving it the second-largest proven oil reserves in the world. The Athabasca oil sands are the largest bitumen deposit in Canada and the only one accessible to surface mining, although recent technological breakthroughs have resulted in deeper deposits becoming producible by in situ methods. Because of oil price increases after 2003, producing bitumen became highly profitable, but as a result of the decline after 2014 it became uneconomic to build new plants again. By 2014, Canadian crude bitumen production averaged about per day and was projected to rise to per day by 2020. The total amount of crude bitumen in Alberta that could be extracted is estimated to be about , which at a rate of would last about 200 years. Alternatives and bioasphalt Although uncompetitive economically, bitumen can be made from nonpetroleum-based renewable resources such as sugar, molasses and rice, corn and potato starches. Bitumen can also be made from waste material by fractional distillation |
of used motor oil, which is sometimes otherwise disposed of by burning or dumping into landfills. Use of motor oil may cause premature cracking in colder climates, resulting in roads that need to be repaved more frequently. Nonpetroleum-based asphalt binders can be made light-colored. Lighter-colored roads absorb less heat from solar radiation, reducing their contribution to the urban heat island effect. Parking lots that use bitumen alternatives are called green parking lots. Albanian deposits Selenizza is a naturally occurring solid hydrocarbon bitumen found in native deposits in Selenice, in Albania, the only European asphalt mine still in use. The bitumen is found in the form of veins, filling cracks in a more or less horizontal direction. The bitumen content varies from 83% to 92% (soluble in carbon disulphide), with a penetration value near to zero and a softening point (ring and ball) around 120 °C. The insoluble matter, consisting mainly of silica ore, ranges from 8% to 17%. Albanian bitumen extraction has a long history and was practiced in an organized way by the Romans. After centuries of silence, the first mentions of Albanian bitumen appeared only in 1868, when the Frenchman Coquand published the first geological description of the deposits of Albanian bitumen. In 1875, the exploitation rights were granted to the Ottoman government and in 1912, they were transferred to the Italian company Simsa. Since 1945, the mine was exploited by the Albanian government and from 2001 to date, the management passed to a French company, which organized the mining process for the manufacture of the natural bitumen on an industrial scale. Today the mine is predominantly exploited in an open pit quarry but several of the many underground mines (deep and extending over several km) still remain viable. Selenizza is produced primarily in granular form, after melting the bitumen pieces selected in the mine. Selenizza is mainly used as an additive in the road construction sector. It is mixed with traditional bitumen to improve both the viscoelastic properties and the resistance to ageing. It may be blended with the hot bitumen in tanks, but its granular form allows it to be fed in the mixer or in the recycling ring of normal asphalt plants. Other typical applications include the production of mastic asphalts for sidewalks, bridges, car-parks and urban roads as well as drilling fluid additives for the oil and gas industry. Selenizza is available in powder |
or in granular material of various particle sizes and is packaged in sacks or in thermal fusible polyethylene bags. A life-cycle assessment study of the natural selenizza compared with petroleum bitumen has shown that the environmental impact of the selenizza is about half the impact of the road asphalt produced in oil refineries in terms of carbon dioxide emission. Recycling Bitumen is a commonly recycled material in the construction industry. The two most common recycled materials that contain bitumen are reclaimed asphalt pavement (RAP) and reclaimed asphalt shingles (RAS). RAP is recycled at a greater rate than any other material in the United States, and typically contains approximately 5–6% bitumen binder. Asphalt shingles typically contain 20–40% bitumen binder. Bitumen naturally becomes stiffer over time due to oxidation, evaporation, exudation, and physical hardening. For this reason, recycled asphalt is typically combined with virgin asphalt, softening agents, and/or rejuvenating additives to restore its physical and chemical properties. For information on the processing and performance of RAP and RAS, see Asphalt Concrete. For information on the different types of RAS and associated health and safety concerns, see Asphalt Shingles. For information on in-place recycling methods used to restore pavements and roadways, see Road Surface. Economics Although bitumen typically makes up only 4 to 5 percent (by weight) of the pavement mixture, as the pavement's binder, it is also the most expensive part of the cost of the road-paving material. During bitumen's early use in modern paving, oil refiners gave it away. However, bitumen is a highly traded commodity today. Its prices increased substantially in the early 21st Century. A U.S. government report states: "In 2002, asphalt sold for approximately $160 per ton. By the end of 2006, the cost had doubled to approximately $320 per ton, and then it almost doubled again in 2012 to approximately $610 per ton." The report indicates that an "average" 1-mile (1.6-kilometer)-long, four-lane highway would include "300 tons of asphalt," which, "in 2002 would have cost around $48,000. By 2006 this would have increased to $96,000 and by 2012 to $183,000... an increase of about $135,000 for every mile of highway in just 10 years." Health and safety People can be exposed to bitumen in the workplace by breathing in fumes or skin absorption. The National Institute for Occupational Safety and Health (NIOSH) has set a recommended exposure limit of 5 mg/m3 over a 15-minute period. Bitumen is |
basically an inert material that must be heated or diluted to a point where it becomes workable for the production of materials for paving, roofing, and other applications. In examining the potential health hazards associated with bitumen, the International Agency for Research on Cancer (IARC) determined that it is the application parameters, predominantly temperature, that affect occupational exposure and the potential bioavailable carcinogenic hazard/risk of the bitumen emissions. In particular, temperatures greater than 199 °C (390 °F), were shown to produce a greater exposure risk than when bitumen was heated to lower temperatures, such as those typically used in asphalt pavement mix production and placement. IARC has classified paving asphalt fumes as a Class 2B possible carcinogen, indicating inadequate evidence of carcinogenicity in humans. In 2020, scientists reported that bitumen currently is a significant and largely overlooked source of air pollution in urban areas, especially during hot and sunny periods. A bitumen-like substance found in the Himalayas and known as shilajit is sometimes used as an Ayurveda medicine, but is not in fact a tar, resin or bitumen. See also Asphalt plant Asphaltene Bioasphalt Bitumen-based fuel Bituminous rocks Blacktop Cariphalte Duxit Macadam Oil sands Pitch drop experiment Pitch (resin) Road surface Tar Tarmac Sealcoat Stamped asphalt Notes References Sources Barth, Edwin J. (1962), Asphalt: Science and Technology, Gordon and Breach. . External links Pavement Interactive – Asphalt CSU Sacramento, The World Famous Asphalt Museum! National Institute for Occupational Safety and Health – Asphalt Fumes Scientific American, "Asphalt", 20-Aug-1881, pp. 121 Amorphous solids Building materials Chemical mixtures IARC Group 2B carcinogens Pavements Petroleum products Road construction materials |
The American National Standards Institute (ANSI ) is a private nonprofit organization that oversees the development of voluntary consensus standards for products, services, processes, systems, and personnel in the United States. The organization also coordinates U.S. standards with international standards so that American products can be used worldwide. ANSI accredits standards that are developed by representatives of other standards organizations, government agencies, consumer groups, companies, and others. These standards ensure that the characteristics and performance of products are consistent, that people use the same definitions and terms, and that products are tested the same way. ANSI also accredits organizations that carry out product or personnel certification in accordance with requirements defined in international standards. The organization's headquarters are in Washington, D.C. ANSI's operations office is located in New York City. The ANSI annual operating budget is funded by the sale of publications, membership dues and fees, accreditation services, fee-based programs, and international standards programs. History ANSI was most likely originally formed in 1918, when five engineering societies and three government agencies founded the American Engineering Standards Committee (AESC). In 1928, the AESC became the American Standards Association (ASA). In 1966, the ASA was reorganized and became United States of America Standards Institute (USASI). The present name was adopted in 1969. Prior to 1918, these five founding engineering societies: American Institute of Electrical Engineers (AIEE, now IEEE) American Society of Mechanical Engineers (ASME) American Society of Civil Engineers (ASCE) American Institute of Mining Engineers (AIME, now American Institute of Mining, Metallurgical, and Petroleum Engineers) American Society for Testing and Materials (now ASTM International) had been members of the United Engineering Society (UES). At the behest of the AIEE, they invited the U.S. government Departments of War, Navy (combined in 1947 to become the Department of Defense or DOD) and Commerce to join in founding a national standards organization. According to Adam Stanton, the first permanent secretary and head of staff in 1919, AESC started as an ambitious program and little else. Staff for the first year consisted of one executive, Clifford B. LePage, who was on loan from a founding member, ASME. An annual budget of $7,500 was provided by the founding bodies. In 1931, the organization (renamed ASA in 1928) became affiliated with the U.S. National Committee of the International Electrotechnical Commission (IEC), which had been formed in 1904 to develop electrical and electronics standards. Members ANSI's members are government |
agencies, organizations, academic and international bodies, and individuals. In total, the Institute represents the interests of more than 270,000 companies and organizations and 30 million professionals worldwide. Process Although ANSI itself does not develop standards, the Institute oversees the development and use of standards by accrediting the procedures of standards developing organizations. ANSI accreditation signifies that the procedures used by standards developing organizations meet the institute's requirements for openness, balance, consensus, and due process. ANSI also designates specific standards as American National Standards, or ANS, when the Institute determines that the standards were developed in an environment that is equitable, accessible and responsive to the requirements of various stakeholders. Voluntary consensus standards quicken the market acceptance of products while making clear how to improve the safety of those products for the protection of consumers. There are approximately 9,500 American National Standards that carry the ANSI designation. The American National Standards process involves: consensus by a group that is open to representatives from all interested parties broad-based public review and comment on draft standards consideration of and response to comments incorporation of submitted changes that meet the same consensus requirements into a draft standard availability of an appeal by any participant alleging that these principles were not respected during the standards-development process. International activities In addition to facilitating the formation of standards in the United States, ANSI promotes the use of U.S. standards internationally, advocates U.S. policy and technical positions in international and regional standards organizations, and encourages the adoption of international standards as national standards where appropriate. The institute is the official U.S. representative to the two major international standards organizations, the International Organization for Standardization (ISO), as a founding member, and the International Electrotechnical Commission (IEC), via the U.S. National Committee (USNC). ANSI participates in almost the entire technical program of both the ISO and the IEC, and administers many key committees and subgroups. In many instances, U.S. standards are taken forward to ISO and IEC, through ANSI or the USNC, where they are adopted in whole or in part as international standards. Adoption of ISO and IEC standards as American standards increased from 0.2% in 1986 to 15.5% in May 2012. Standards panels The Institute administers nine standards panels: ANSI Homeland Defense and Security Standardization Collaborative (HDSSC) ANSI Nanotechnology Standards Panel (ANSI-NSP) ID Theft Prevention and ID Management Standards Panel (IDSP) ANSI Energy Efficiency Standardization Coordination Collaborative (EESCC) |
Nuclear Energy Standards Coordination Collaborative (NESCC) Electric Vehicles Standards Panel (EVSP) ANSI-NAM Network on Chemical Regulation ANSI Biofuels Standards Coordination Panel Healthcare Information Technology Standards Panel (HITSP) Each of the panels works to identify, coordinate, and harmonize voluntary standards relevant to these areas. In 2009, ANSI and the National Institute of Standards and Technology (NIST) formed the Nuclear Energy Standards Coordination Collaborative (NESCC). NESCC is a joint initiative to identify and respond to the current need for standards in the nuclear industry. American national standards The ASA (as for American Standards Association) photographic exposure system, originally defined in ASA Z38.2.1 (since 1943) and ASA PH2.5 (since 1954), together with the DIN system (DIN 4512 since 1934), became the basis for the ISO system (since 1974), currently used worldwide (ISO 6, ISO 2240, ISO 5800, ISO 12232). A standard for the set of values used to represent characters in digital computers. The ANSI code standard extended the previously created ASCII seven bit code standard (ASA X3.4-1963), with additional codes for European alphabets (see also Extended Binary Coded Decimal Interchange Code or EBCDIC). In Microsoft Windows, the phrase "ANSI" refers to the Windows ANSI code pages (even though they are not ANSI standards). Most of these are fixed width, though some characters for ideographic languages are variable width. Since these characters are based on a draft of the ISO-8859 series, some of Microsoft's symbols are visually very similar to the ISO symbols, leading many to falsely assume that they are identical. The first computer programming language standard was "American Standard Fortran" (informally known as "FORTRAN 66"), approved in March 1966 and published as ASA X3.9-1966. The programming language COBOL had ANSI standards in 1968, 1974, and 1985. The COBOL 2002 standard was issued by ISO. The original standard implementation of the C programming language was standardized as ANSI X3.159-1989, becoming the well-known ANSI C. The X3J13 committee was created in 1986 to formalize the ongoing consolidation of Common Lisp, culminating in 1994 with the publication of ANSI's first object-oriented programming standard. A popular Unified Thread Standard for nuts and bolts is ANSI/ASME B1.1 which was defined in 1935, 1949, 1989, and 2003. The ANSI-NSF International standards used for commercial kitchens, such as restaurants, cafeterias, delis, etc. The ANSI/APSP (Association of Pool & Spa Professionals) standards used for pools, spas, hot tubs, barriers, and suction entrapment avoidance. The ANSI/HI (Hydraulic Institute) standards used |
for pumps. The ANSI for eye protection is Z87.1, which gives a specific impact resistance rating to the eyewear. This standard is commonly used for shop glasses, shooting glasses, and many other examples of protective eyewear. The ANSI paper sizes (ANSI/ASME Y14.1). Other initiatives In 2008, ANSI, in partnership with Citation Technologies, created the first dynamic, online web library for ISO 14000 standards. On June 23, 2009, ANSI announced a product and services agreement with Citation Technologies to deliver all ISO Standards on a web-based platform. Through the ANSI-Citation partnership, 17,765 International Standards developed by more than 3,000 ISO technical bodies will be made available on the citation platform, arming subscribers with powerful search tools and collaboration, notification, and change-management functionality. ANSI, in partnership with Citation Technologies, AAMI, ASTM, and DIN, created a single, centralized database for medical device standards on September 9, 2009. In early 2009, ANSI launched a new Certificate Accreditation Program (ANSI-CAP) to provide neutral, third-party attestation that a given certificate program meets the American National Standard ASTM E2659-09. In 2009, ANSI began accepting applications for certification bodies seeking accreditation according to requirements defined under the Toy Safety Certification Program (TSCP) as the official third-party accreditor of TSCP's product certification bodies. In 2006, ANSI launched www.StandardsPortal.org, an online resource for facilitating more open and efficient trade between international markets in the areas of standards, conformity assessment, and technical regulations. The site currently features content for the United States, China, India, Korea, and Brazil, with additional countries and regions planned for future content. ANSI design standards have also been incorporated into building codes encompassing several specific building sub-sets, such as the ANSI/SPRI ES-1, which pertains to "Wind Design Standard for Edge Systems Used With Low Slope Roofing Systems", for example. See also Accredited Crane Operator Certification ANSI ASC X9 ANSI ASC X12 ANSI C Institute of Environmental Sciences and Technology (IEST) Institute of Nuclear Materials Management (INMM) ISO (to which ANSI is the official US representative) National Information Standards Organization (NISO) National Institute of Standards and Technology (NIST) Open standards References External links 1918 establishments in the United States 501(c)(3) organizations Charities based in Washington, D.C. ISO member bodies Organizations established in 1918 Technical specifications |
In logic and philosophy, an argument is an attempt to persuade someone of something, or give evidence or reasons for accepting a particular conclusion. Argument may also refer to: Mathematics and computer science Argument (complex analysis), a function which returns the polar angle of a complex number Command-line argument, an item of information provided to a program when it is started Parameter (computer programming), a piece of data provided as input to a subroutine Argument principle, a theorem in complex analysis An argument of a function, also known as an independent variable Language and rhetoric Argument (literature), a brief summary, often in prose, of a poem or section of a poem or other work Argument (linguistics), a phrase that appears in a syntactic relationship with the verb in a clause Oral argument in the United States, a spoken presentation to a judge or appellate court by a lawyer (or parties when representing themselves) of the legal reasons why they should prevail Closing argument, in law, the concluding statement of each party's counsel reiterating the important arguments in a court case Other uses Musical argument, a concept in the theory of musical form Argument (ship), an Australian sloop wrecked in 1809 Das Argument, a German academic journal Argument Clinic, a Monty Python sketch A disagreement between two or more parties or the discussion of the disagreement Argument (horse) See also The Argument (disambiguation) |
Apollo 11 (July 16–24, 1969) was the American spaceflight that first landed humans on the Moon. Commander Neil Armstrong and lunar module pilot Buzz Aldrin landed the Apollo Lunar Module Eagle on July 20, 1969, at 20:17 UTC, and Armstrong became the first person to step onto the Moon's surface six hours and 39 minutes later, on July 21 at 02:56 UTC. Aldrin joined him 19 minutes later, and they spent about two and a quarter hours together exploring the site they had named Tranquility Base upon landing. Armstrong and Aldrin collected of lunar material to bring back to Earth as pilot Michael Collins flew the Command Module Columbia in lunar orbit, and were on the Moon's surface for 21 hours, 36 minutes before lifting off to rejoin Columbia. Apollo 11 was launched by a Saturn V rocket from Kennedy Space Center on Merritt Island, Florida, on July 16 at 13:32 UTC, and it was the fifth crewed mission of NASA's Apollo program. The Apollo spacecraft had three parts: a command module (CM) with a cabin for the three astronauts, the only part that returned to Earth; a service module (SM), which supported the command module with propulsion, electrical power, oxygen, and water; and a lunar module (LM) that had two stages—a descent stage for landing on the Moon and an ascent stage to place the astronauts back into lunar orbit. After being sent to the Moon by the Saturn V's third stage, the astronauts separated the spacecraft from it and traveled for three days until they entered lunar orbit. Armstrong and Aldrin then moved into Eagle and landed in the Sea of Tranquility on July 20. The astronauts used Eagles ascent stage to lift off from the lunar surface and rejoin Collins in the command module. They jettisoned Eagle before they performed the maneuvers that propelled Columbia out of the last of its 30 lunar orbits onto a trajectory back to Earth. They returned to Earth and splashed down in the Pacific Ocean on July 24 after more than eight days in space. Armstrong's first step onto the lunar surface was broadcast on live TV to a worldwide audience. He described the event as "one small step for [a] man, one giant leap for mankind." Apollo 11 effectively proved US victory in the Space Race to demonstrate spaceflight superiority, by fulfilling a national goal proposed in 1961 by President |
John F. Kennedy, "before this decade is out, of landing a man on the Moon and returning him safely to the Earth." Background In the late 1950s and early 1960s, the United States was engaged in the Cold War, a geopolitical rivalry with the Soviet Union. On October 4, 1957, the Soviet Union launched Sputnik 1, the first artificial satellite. This surprise success fired fears and imaginations around the world. It demonstrated that the Soviet Union had the capability to deliver nuclear weapons over intercontinental distances, and challenged American claims of military, economic and technological superiority. This precipitated the Sputnik crisis, and triggered the Space Race to prove which superpower would achieve superior spaceflight capability. President Dwight D. Eisenhower responded to the Sputnik challenge by creating the National Aeronautics and Space Administration (NASA), and initiating Project Mercury, which aimed to launch a man into Earth orbit. But on April 12, 1961, Soviet cosmonaut Yuri Gagarin became the first person in space, and the first to orbit the Earth. Nearly a month later, on May 5, 1961, Alan Shepard became the first American in space, completing a 15-minute suborbital journey. After being recovered from the Atlantic Ocean, he received a congratulatory telephone call from Eisenhower's successor, John F. Kennedy. Since the Soviet Union had higher lift capacity launch vehicles, Kennedy chose, from among options presented by NASA, a challenge beyond the capacity of the existing generation of rocketry, so that the US and Soviet Union would be starting from a position of equality. A crewed mission to the Moon would serve this purpose. On May 25, 1961, Kennedy addressed the United States Congress on "Urgent National Needs" and declared: On September 12, 1962, Kennedy delivered another speech before a crowd of about 40,000 people in the Rice University football stadium in Houston, Texas. A widely quoted refrain from the middle portion of the speech reads as follows: In spite of that, the proposed program faced the opposition of many Americans and was dubbed a "moondoggle" by Norbert Wiener, a mathematician at the Massachusetts Institute of Technology. The effort to land a man on the Moon already had a name: Project Apollo. When Kennedy met with Nikita Khrushchev, the Premier of the Soviet Union in June 1961, he proposed making the Moon landing a joint project, but Khrushchev did not take up the offer. Kennedy again proposed a joint expedition to the |
Moon in a speech to the United Nations General Assembly on September 20, 1963. The idea of a joint Moon mission was abandoned after Kennedy's death. An early and crucial decision was choosing lunar orbit rendezvous over both direct ascent and Earth orbit rendezvous. A space rendezvous is an orbital maneuver in which two spacecraft navigate through space and meet up. In July 1962 NASA head James Webb announced that lunar orbit rendezvous would be used and that the Apollo spacecraft would have three major parts: a command module (CM) with a cabin for the three astronauts, and the only part that returned to Earth; a service module (SM), which supported the command module with propulsion, electrical power, oxygen, and water; and a lunar module (LM) that had two stages—a descent stage for landing on the Moon, and an ascent stage to place the astronauts back into lunar orbit. This design meant the spacecraft could be launched by a single Saturn V rocket that was then under development. Technologies and techniques required for Apollo were developed by Project Gemini. The Apollo project was enabled by NASA's adoption of new advances in semiconductor electronic technology, including metal–oxide–semiconductor field-effect transistors (MOSFETs) in the Interplanetary Monitoring Platform (IMP) and silicon integrated circuit (IC) chips in the Apollo Guidance Computer (AGC). Project Apollo was abruptly halted by the Apollo 1 fire on January 27, 1967, in which astronauts Gus Grissom, Ed White, and Roger B. Chaffee died, and the subsequent investigation. In October 1968, Apollo 7 evaluated the command module in Earth orbit, and in December Apollo 8 tested it in lunar orbit. In March 1969, Apollo 9 put the lunar module through its paces in Earth orbit, and in May Apollo 10 conducted a "dress rehearsal" in lunar orbit. By July 1969, all was in readiness for Apollo 11 to take the final step onto the Moon. The Soviet Union appeared to be winning the Space Race by beating the US to firsts, but its early lead was overtaken by the US Gemini program and Soviet failure to develop the N1 launcher, which would have been comparable to the Saturn V. The Soviets tried to beat the US to return lunar material to the Earth by means of uncrewed probes. On July 13, three days before Apollo 11's launch, the Soviet Union launched Luna 15, which reached lunar orbit before Apollo 11. During |
descent, a malfunction caused Luna 15 to crash in Mare Crisium about two hours before Armstrong and Aldrin took off from the Moon's surface to begin their voyage home. The Nuffield Radio Astronomy Laboratories radio telescope in England recorded transmissions from Luna 15 during its descent, and these were released in July 2009 for the 40th anniversary of Apollo 11. Personnel Prime crew The initial crew assignment of Commander Neil Armstrong, Command Module Pilot (CMP) Jim Lovell, and Lunar Module Pilot (LMP) Buzz Aldrin on the backup crew for Apollo 9 was officially announced on November 20, 1967. Lovell and Aldrin had previously flown together as the crew of Gemini 12. Due to design and manufacturing delays in the LM, Apollo 8 and Apollo 9 swapped prime and backup crews, and Armstrong's crew became the backup for Apollo 8. Based on the normal crew rotation scheme, Armstrong was then expected to command Apollo 11. There would be one change. Michael Collins, the CMP on the Apollo 8 crew, began experiencing trouble with his legs. Doctors diagnosed the problem as a bony growth between his fifth and sixth vertebrae, requiring surgery. Lovell took his place on the Apollo 8 crew, and when Collins recovered he joined Armstrong's crew as CMP. In the meantime, Fred Haise filled in as backup LMP, and Aldrin as backup CMP for Apollo 8. Apollo 11 was the second American mission where all the crew members had prior spaceflight experience, the first being Apollo 10. The next was STS-26 in 1988. Deke Slayton gave Armstrong the option to replace Aldrin with Lovell, since some thought Aldrin was difficult to work with. Armstrong had no issues working with Aldrin but thought it over for a day before declining. He thought Lovell deserved to command his own mission (eventually Apollo 13). The Apollo 11 prime crew had none of the close cheerful camaraderie characterized by that of Apollo 12. Instead, they forged an amiable working relationship. Armstrong in particular was notoriously aloof, but Collins, who considered himself a loner, confessed to rebuffing Aldrin's attempts to create a more personal relationship. Aldrin and Collins described the crew as "amiable strangers". Armstrong did not agree with the assessment, and said "... all the crews I was on worked very well together." Backup crew The backup crew consisted of Lovell as Commander, William Anders as CMP, and Haise as LMP. Anders had |
flown with Lovell on Apollo 8. In early 1969, Anders accepted a job with the National Aeronautics and Space Council effective August 1969, and announced he would retire as an astronaut at that time. Ken Mattingly was moved from the support crew into parallel training with Anders as backup CMP in case Apollo 11 was delayed past its intended July launch date, at which point Anders would be unavailable. By the normal crew rotation in place during Apollo, Lovell, Mattingly, and Haise were scheduled to fly on Apollo 14, but the three of them were bumped to Apollo 13: there was a crew issue for Apollo 13 as none of them except Edgar Mitchell flew in space again. George Mueller rejected the crew and this was the first time an Apollo crew was rejected. To give Shepard more training time, Lovell's crew were bumped to Apollo 13. Mattingly would later be replaced by Jack Swigert as CMP on Apollo 13. Support crew During Projects Mercury and Gemini, each mission had a prime and a backup crew. For Apollo, a third crew of astronauts was added, known as the support crew. The support crew maintained the flight plan, checklists and mission ground rules, and ensured the prime and backup crews were apprised of changes. They developed procedures, especially those for emergency situations, so these were ready for when the prime and backup crews came to train in the simulators, allowing them to concentrate on practicing and mastering them. For Apollo 11, the support crew consisted of Ken Mattingly, Ronald Evans and Bill Pogue. Capsule communicators The capsule communicator (CAPCOM) was an astronaut at the Mission Control Center in Houston, Texas, who was the only person who communicated directly with the flight crew. For Apollo 11, the CAPCOMs were: Charles Duke, Ronald Evans, Bruce McCandless II, James Lovell, William Anders, Ken Mattingly, Fred Haise, Don L. Lind, Owen K. Garriott and Harrison Schmitt. Flight directors The flight directors for this mission were: Other key personnel Other key personnel who played important roles in the Apollo 11 mission include the following. Preparations Insignia The Apollo 11 mission emblem was designed by Collins, who wanted a symbol for "peaceful lunar landing by the United States". At Lovell's suggestion, he chose the bald eagle, the national bird of the United States, as the symbol. Tom Wilson, a simulator instructor, suggested an olive branch in its |
beak to represent their peaceful mission. Collins added a lunar background with the Earth in the distance. The sunlight in the image was coming from the wrong direction; the shadow should have been in the lower part of the Earth instead of the left. Aldrin, Armstrong and Collins decided the Eagle and the Moon would be in their natural colors, and decided on a blue and gold border. Armstrong was concerned that "eleven" would not be understood by non-English speakers, so they went with "Apollo 11", and they decided not to put their names on the patch, so it would "be representative of everyone who had worked toward a lunar landing". An illustrator at the Manned Spacecraft Center (MSC) did the artwork, which was then sent off to NASA officials for approval. The design was rejected. Bob Gilruth, the director of the MSC felt the talons of the eagle looked "too warlike". After some discussion, the olive branch was moved to the talons. When the Eisenhower dollar coin was released in 1971, the patch design provided the eagle for its reverse side. The design was also used for the smaller Susan B. Anthony dollar unveiled in 1979. Call signs After the crew of Apollo 10 named their spacecraft Charlie Brown and Snoopy, assistant manager for public affairs Julian Scheer wrote to George Low, the Manager of the Apollo Spacecraft Program Office at the MSC, to suggest the Apollo 11 crew be less flippant in naming their craft. The name Snowcone was used for the CM and Haystack was used for the LM in both internal and external communications during early mission planning. The LM was named Eagle after the motif which was featured prominently on the mission insignia. At Scheer's suggestion, the CM was named Columbia after Columbiad, the giant cannon that launched a spacecraft (also from Florida) in Jules Verne's 1865 novel From the Earth to the Moon. It also referred to Columbia, a historical name of the United States. In Collins' 1976 book, he said Columbia was in reference to Christopher Columbus. Mementos The astronauts had personal preference kits (PPKs), small bags containing personal items of significance they wanted to take with them on the mission. Five PPKs were carried on Apollo 11: three (one for each astronaut) were stowed on Columbia before launch, and two on Eagle. Neil Armstrong's LM PPK contained a piece of wood from |
the Wright brothers' 1903 Wright Flyers left propeller and a piece of fabric from its wing, along with a diamond-studded astronaut pin originally given to Slayton by the widows of the Apollo 1 crew. This pin had been intended to be flown on that mission and given to Slayton afterwards, but following the disastrous launch pad fire and subsequent funerals, the widows gave the pin to Slayton. Armstrong took it with him on Apollo 11. Site selection NASA's Apollo Site Selection Board announced five potential landing sites on February 8, 1968. These were the result of two years' worth of studies based on high-resolution photography of the lunar surface by the five uncrewed probes of the Lunar Orbiter program and information about surface conditions provided by the Surveyor program. The best Earth-bound telescopes could not resolve features with the resolution Project Apollo required. The landing site had to be close to the lunar equator to minimize the amount of propellant required, clear of obstacles to minimize maneuvering, and flat to simplify the task of the landing radar. Scientific value was not a consideration. Areas that appeared promising on photographs taken on Earth were often found to be totally unacceptable. The original requirement that the site be free of craters had to be relaxed, as no such site was found. Five sites were considered: Sites 1 and 2 were in the Sea of Tranquility (Mare Tranquillitatis); Site 3 was in the Central Bay (Sinus Medii); and Sites 4 and 5 were in the Ocean of Storms (Oceanus Procellarum). The final site selection was based on seven criteria: The site needed to be smooth, with relatively few craters; with approach paths free of large hills, tall cliffs or deep craters that might confuse the landing radar and cause it to issue incorrect readings; reachable with a minimum amount of propellant; allowing for delays in the launch countdown; providing the Apollo spacecraft with a free-return trajectory, one that would allow it to coast around the Moon and safely return to Earth without requiring any engine firings should a problem arise on the way to the Moon; with good visibility during the landing approach, meaning the Sun would be between 7 and 20 degrees behind the LM; and a general slope of less than two degrees in the landing area. The requirement for the Sun angle was particularly restrictive, limiting the launch date to |
one day per month. A landing just after dawn was chosen to limit the temperature extremes the astronauts would experience. The Apollo Site Selection Board selected Site 2, with Sites 3 and 5 as backups in the event of the launch being delayed. In May 1969, Apollo 10's lunar module flew to within of Site 2, and reported it was acceptable. First-step decision During the first press conference after the Apollo 11 crew was announced, the first question was, "Which one of you gentlemen will be the first man to step onto the lunar surface?" Slayton told the reporter it had not been decided, and Armstrong added that it was "not based on individual desire". One of the first versions of the egress checklist had the lunar module pilot exit the spacecraft before the commander, which matched what had been done on Gemini missions, where the commander had never performed the spacewalk. Reporters wrote in early 1969 that Aldrin would be the first man to walk on the Moon, and Associate Administrator George Mueller told reporters he would be first as well. Aldrin heard that Armstrong would be the first because Armstrong was a civilian, which made Aldrin livid. Aldrin attempted to persuade other lunar module pilots he should be first, but they responded cynically about what they perceived as a lobbying campaign. Attempting to stem interdepartmental conflict, Slayton told Aldrin that Armstrong would be first since he was the commander. The decision was announced in a press conference on April 14, 1969. For decades, Aldrin believed the final decision was largely driven by the lunar module's hatch location. Because the astronauts had their spacesuits on and the spacecraft was so small, maneuvering to exit the spacecraft was difficult. The crew tried a simulation in which Aldrin left the spacecraft first, but he damaged the simulator while attempting to egress. While this was enough for mission planners to make their decision, Aldrin and Armstrong were left in the dark on the decision until late spring. Slayton told Armstrong the plan was to have him leave the spacecraft first, if he agreed. Armstrong said, "Yes, that's the way to do it." The media accused Armstrong of exercising his commander's prerogative to exit the spacecraft first. Chris Kraft revealed in his 2001 autobiography that a meeting occurred between Gilruth, Slayton, Low, and himself to make sure Aldrin would not be the first |
to walk on the Moon. They argued that the first person to walk on the Moon should be like Charles Lindbergh, a calm and quiet person. They made the decision to change the flight plan so the commander was the first to egress from the spacecraft. Pre-launch The ascent stage of LM-5 Eagle arrived at the Kennedy Space Center on January 8, 1969, followed by the descent stage four days later, and CSM-107 Columbia on January 23. There were several differences between Eagle and Apollo 10's LM-4 Snoopy; Eagle had a VHF radio antenna to facilitate communication with the astronauts during their EVA on the lunar surface; a lighter ascent engine; more thermal protection on the landing gear; and a package of scientific experiments known as the Early Apollo Scientific Experiments Package (EASEP). The only change in the configuration of the command module was the removal of some insulation from the forward hatch. The CSM was mated on January 29, and moved from the Operations and Checkout Building to the Vehicle Assembly Building on April 14. The S-IVB third stage of Saturn V AS-506 had arrived on January 18, followed by the S-II second stage on February 6, S-IC first stage on February 20, and the Saturn V Instrument Unit on February 27. At 12:30 on May 20, the assembly departed the Vehicle Assembly Building atop the crawler-transporter, bound for Launch Pad 39A, part of Launch Complex 39, while Apollo 10 was still on its way to the Moon. A countdown test commenced on June 26, and concluded on July 2. The launch complex was floodlit on the night of July 15, when the crawler-transporter carried the mobile service structure back to its parking area. In the early hours of the morning, the fuel tanks of the S-II and S-IVB stages were filled with liquid hydrogen. Fueling was completed by three hours before launch. Launch operations were partly automated, with 43 programs written in the ATOLL programming language. Slayton roused the crew shortly after 04:00, and they showered, shaved, and had the traditional pre-flight breakfast of steak and eggs with Slayton and the backup crew. They then donned their space suits and began breathing pure oxygen. At 06:30, they headed out to Launch Complex 39. Haise entered Columbia about three hours and ten minutes before launch time. Along with a technician, he helped Armstrong into the left-hand couch at 06:54. |
Five minutes later, Collins joined him, taking up his position on the right-hand couch. Finally, Aldrin entered, taking the center couch. Haise left around two hours and ten minutes before launch. The closeout crew sealed the hatch, and the cabin was purged and pressurized. The closeout crew then left the launch complex about an hour before launch time. The countdown became automated at three minutes and twenty seconds before launch time. Over 450 personnel were at the consoles in the firing room. Mission Launch and flight to lunar orbit An estimated one million spectators watched the launch of Apollo 11 from the highways and beaches in the vicinity of the launch site. Dignitaries included the Chief of Staff of the United States Army, General William Westmoreland, four cabinet members, 19 state governors, 40 mayors, 60 ambassadors and 200 congressmen. Vice President Spiro Agnew viewed the launch with former president Lyndon B. Johnson and his wife Lady Bird Johnson. Around 3,500 media representatives were present. About two-thirds were from the United States; the rest came from 55 other countries. The launch was televised live in 33 countries, with an estimated 25 million viewers in the United States alone. Millions more around the world listened to radio broadcasts. President Richard Nixon viewed the launch from his office in the White House with his NASA liaison officer, Apollo astronaut Frank Borman. Saturn V AS-506 launched Apollo 11 on July 16, 1969, at 13:32:00 UTC (9:32:00 EDT). At 13.2 seconds into the flight, the launch vehicle began to roll into its flight azimuth of 72.058°. Full shutdown of the first-stage engines occurred about 2 minutes and 42 seconds into the mission, followed by separation of the S-IC and ignition of the S-II engines. The second stage engines then cut off and separated at about 9 minutes and 8 seconds, allowing the first ignition of the S-IVB engine a few seconds later. Apollo 11 entered a near-circular Earth orbit at an altitude of by , twelve minutes into its flight. After one and a half orbits, a second ignition of the S-IVB engine pushed the spacecraft onto its trajectory toward the Moon with the trans-lunar injection (TLI) burn at 16:22:13 UTC. About 30 minutes later, with Collins in the left seat and at the controls, the transposition, docking, and extraction maneuver was performed. This involved separating Columbia from the spent S-IVB stage, turning around, and |
docking with Eagle still attached to the stage. After the LM was extracted, the combined spacecraft headed for the Moon, while the rocket stage flew on a trajectory past the Moon. This was done to avoid the third stage colliding with the spacecraft, the Earth, or the Moon. A slingshot effect from passing around the Moon threw it into an orbit around the Sun. On July 19 at 17:21:50 UTC, Apollo 11 passed behind the Moon and fired its service propulsion engine to enter lunar orbit. In the thirty orbits that followed, the crew saw passing views of their landing site in the southern Sea of Tranquility about southwest of the crater Sabine D. The site was selected in part because it had been characterized as relatively flat and smooth by the automated Ranger 8 and Surveyor 5 landers and the Lunar Orbiter mapping spacecraft, and because it was unlikely to present major landing or EVA challenges. It lay about southeast of the Surveyor 5 landing site, and southwest of Ranger 8's crash site. Lunar descent At 12:52:00 UTC on July 20, Aldrin and Armstrong entered Eagle, and began the final preparations for lunar descent. At 17:44:00 Eagle separated from Columbia. Collins, alone aboard Columbia, inspected Eagle as it pirouetted before him to ensure the craft was not damaged, and that the landing gear was correctly deployed. Armstrong exclaimed: "The Eagle has wings!" As the descent began, Armstrong and Aldrin found themselves passing landmarks on the surface two or three seconds early, and reported that they were "long"; they would land miles west of their target point. Eagle was traveling too fast. The problem could have been mascons—concentrations of high mass in a region or regions of the Moon's crust that contains a gravitational anomaly, potentially altering Eagle trajectory. Flight Director Gene Kranz speculated that it could have resulted from extra air pressure in the docking tunnel, or a result of Eagles pirouette maneuver. Five minutes into the descent burn, and above the surface of the Moon, the LM guidance computer (LGC) distracted the crew with the first of several unexpected 1201 and 1202 program alarms. Inside Mission Control Center, computer engineer Jack Garman told Guidance Officer Steve Bales it was safe to continue the descent, and this was relayed to the crew. The program alarms indicated "executive overflows", meaning the guidance computer could not complete all its tasks in |
real-time and had to postpone some of them. Margaret Hamilton, the Director of Apollo Flight Computer Programming at the MIT Charles Stark Draper Laboratory later recalled: During the mission, the cause was diagnosed as the rendezvous radar switch being in the wrong position, causing the computer to process data from both the rendezvous and landing radars at the same time. Software engineer Don Eyles concluded in a 2005 Guidance and Control Conference paper that the problem was due to a hardware design bug previously seen during testing of the first uncrewed LM in Apollo 5. Having the rendezvous radar on (so it was warmed up in case of an emergency landing abort) should have been irrelevant to the computer, but an electrical phasing mismatch between two parts of the rendezvous radar system could cause the stationary antenna to appear to the computer as dithering back and forth between two positions, depending upon how the hardware randomly powered up. The extra spurious cycle stealing, as the rendezvous radar updated an involuntary counter, caused the computer alarms. Landing When Armstrong again looked outside, he saw that the computer's landing target was in a boulder-strewn area just north and east of a crater (later determined to be West crater), so he took semi-automatic control. Armstrong considered landing short of the boulder field so they could collect geological samples from it, but could not since their horizontal velocity was too high. Throughout the descent, Aldrin called out navigation data to Armstrong, who was busy piloting Eagle. Now above the surface, Armstrong knew their propellant supply was dwindling and was determined to land at the first possible landing site. Armstrong found a clear patch of ground and maneuvered the spacecraft towards it. As he got closer, now above the surface, he discovered his new landing site had a crater in it. He cleared the crater and found another patch of level ground. They were now from the surface, with only 90 seconds of propellant remaining. Lunar dust kicked up by the LM's engine began to impair his ability to determine the spacecraft's motion. Some large rocks jutted out of the dust cloud, and Armstrong focused on them during his descent so he could determine the spacecraft's speed. A light informed Aldrin that at least one of the probes hanging from Eagle footpads had touched the surface a few moments before the landing and he said: |
"Contact light!" Armstrong was supposed to immediately shut the engine down, as the engineers suspected the pressure caused by the engine's own exhaust reflecting off the lunar surface could make it explode, but he forgot. Three seconds later, Eagle landed and Armstrong shut the engine down. Aldrin immediately said "Okay, engine stop. ACA—out of detent." Armstrong acknowledged: "Out of detent. Auto." Aldrin continued: "Mode control—both auto. Descent engine command override off. Engine arm—off. 413 is in." ACA was the Attitude Control Assembly—the LM's control stick. Output went to the LGC to command the reaction control system (RCS) jets to fire. "Out of Detent" meant the stick had moved away from its centered position; it was spring-centered like the turn indicator in a car. LGC address 413 contained the variable that indicated the LM had landed. Eagle landed at 20:17:40 UTC on Sunday July 20 with of usable fuel remaining. Information available to the crew and mission controllers during the landing showed the LM had enough fuel for another 25 seconds of powered flight before an abort without touchdown would have become unsafe, but post-mission analysis showed that the real figure was probably closer to 50 seconds. Apollo 11 landed with less fuel than most subsequent missions, and the astronauts encountered a premature low fuel warning. This was later found to be the result of the propellant sloshing more than expected, uncovering a fuel sensor. On subsequent missions, extra anti-slosh baffles were added to the tanks to prevent this. Armstrong acknowledged Aldrin's completion of the post-landing checklist with "Engine arm is off", before responding to the CAPCOM, Charles Duke, with the words, "Houston, Tranquility Base here. The Eagle has landed." Armstrong's unrehearsed change of call sign from "Eagle" to "Tranquility Base" emphasized to listeners that landing was complete and successful. Duke mispronounced his reply as he expressed the relief at Mission Control: "Roger, Twan—Tranquility, we copy you on the ground. You got a bunch of guys about to turn blue. We're breathing again. Thanks a lot." Two and a half hours after landing, before preparations began for the EVA, Aldrin radioed to Earth: He then took communion privately. At this time NASA was still fighting a lawsuit brought by atheist Madalyn Murray O'Hair (who had objected to the Apollo 8 crew reading from the Book of Genesis) demanding that their astronauts refrain from broadcasting religious activities while in space. For this |
reason, Aldrin chose to refrain from directly mentioning taking communion on the Moon. Aldrin was an elder at the Webster Presbyterian Church, and his communion kit was prepared by the pastor of the church, Dean Woodruff. Webster Presbyterian possesses the chalice used on the Moon and commemorates the event each year on the Sunday closest to July 20. The schedule for the mission called for the astronauts to follow the landing with a five-hour sleep period, but they chose to begin preparations for the EVA early, thinking they would be unable to sleep. Lunar surface operations Preparations for Neil Armstrong and Buzz Aldrin to walk on the Moon began at 23:43 UTC. These took longer than expected; three and a half hours instead of two. During training on Earth, everything required had been neatly laid out in advance, but on the Moon the cabin contained a large number of other items as well, such as checklists, food packets, and tools. Six hours and thirty-nine minutes after landing Armstrong and Aldrin were ready to go outside, and Eagle was depressurized. Eagles hatch was opened at 02:39:33. Armstrong initially had some difficulties squeezing through the hatch with his portable life support system (PLSS). Some of the highest heart rates recorded from Apollo astronauts occurred during LM egress and ingress. At 02:51 Armstrong began his descent to the lunar surface. The remote control unit on his chest kept him from seeing his feet. Climbing down the nine-rung ladder, Armstrong pulled a D-ring to deploy the modular equipment stowage assembly (MESA) folded against Eagle side and activate the TV camera. Apollo 11 used slow-scan television (TV) incompatible with broadcast TV, so it was displayed on a special monitor and a conventional TV camera viewed this monitor (thus, a broadcast of a broadcast), significantly reducing the quality of the picture. The signal was received at Goldstone in the United States, but with better fidelity by Honeysuckle Creek Tracking Station near Canberra in Australia. Minutes later the feed was switched to the more sensitive Parkes radio telescope in Australia. Despite some technical and weather difficulties, ghostly black and white images of the first lunar EVA were received and broadcast to at least 600 million people on Earth. Copies of this video in broadcast format were saved and are widely available, but recordings of the original slow scan source transmission from the lunar surface were likely destroyed |
during routine magnetic tape re-use at NASA. After describing the surface dust as "very fine-grained" and "almost like a powder", at 02:56:15, six and a half hours after landing, Armstrong stepped off Eagle footpad and declared: "That's one small step for [a] man, one giant leap for mankind." Armstrong intended to say "That's one small step for a man", but the word "a" is not audible in the transmission, and thus was not initially reported by most observers of the live broadcast. When later asked about his quote, Armstrong said he believed he said "for a man", and subsequent printed versions of the quote included the "a" in square brackets. One explanation for the absence may be that his accent caused him to slur the words "for a" together; another is the intermittent nature of the audio and video links to Earth, partly because of storms near Parkes Observatory. A more recent digital analysis of the tape claims to reveal the "a" may have been spoken but obscured by static. Other analysis points to the claims of static and slurring as "face-saving fabrication", and that Armstrong himself later admitted to misspeaking the line. About seven minutes after stepping onto the Moon's surface, Armstrong collected a contingency soil sample using a sample bag on a stick. He then folded the bag and tucked it into a pocket on his right thigh. This was to guarantee there would be some lunar soil brought back in case an emergency required the astronauts to abandon the EVA and return to the LM. Twelve minutes after the sample was collected, he removed the TV camera from the MESA and made a panoramic sweep, then mounted it on a tripod. The TV camera cable remained partly coiled and presented a tripping hazard throughout the EVA. Still photography was accomplished with a Hasselblad camera that could be operated hand held or mounted on Armstrong's Apollo space suit. Aldrin joined Armstrong on the surface. He described the view with the simple phrase: "Magnificent desolation." Armstrong said moving in the lunar gravity, one-sixth of Earth's, was "even perhaps easier than the simulations ... It's absolutely no trouble to walk around." Aldrin joined him on the surface and tested methods for moving around, including two-footed kangaroo hops. The PLSS backpack created a tendency to tip backward, but neither astronaut had serious problems maintaining balance. Loping became the preferred method of |
movement. The astronauts reported that they needed to plan their movements six or seven steps ahead. The fine soil was quite slippery. Aldrin remarked that moving from sunlight into Eagle shadow produced no temperature change inside the suit, but the helmet was warmer in sunlight, so he felt cooler in shadow. The MESA failed to provide a stable work platform and was in shadow, slowing work somewhat. As they worked, the moonwalkers kicked up gray dust, which soiled the outer part of their suits. The astronauts planted the Lunar Flag Assembly containing a flag of the United States on the lunar surface, in clear view of the TV camera. Aldrin remembered, "Of all the jobs I had to do on the Moon the one I wanted to go the smoothest was the flag raising." But the astronauts struggled with the telescoping rod and could only jam the pole about into the hard lunar surface. Aldrin was afraid it might topple in front of TV viewers, but gave "a crisp West Point salute". Before Aldrin could take a photo of Armstrong with the flag, President Richard Nixon spoke to them through a telephone-radio transmission, which Nixon called "the most historic phone call ever made from the White House." Nixon originally had a long speech prepared to read during the phone call, but Frank Borman, who was at the White House as a NASA liaison during Apollo 11, convinced Nixon to keep his words brief. They deployed the EASEP, which included a passive seismic experiment package used to measure moonquakes and a retroreflector array used for the lunar laser ranging experiment. Then Armstrong walked from the LM to snap photos at the rim of Little West Crater while Aldrin collected two core samples. He used the geologist's hammer to pound in the tubes—the only time the hammer was used on Apollo 11—but was unable to penetrate more than deep. The astronauts then collected rock samples using scoops and tongs on extension handles. Many of the surface activities took longer than expected, so they had to stop documenting sample collection halfway through the allotted 34 minutes. Aldrin shoveled of soil into the box of rocks in order to pack them in tightly. Two types of rocks were found in the geological samples: basalt and breccia. Three new minerals were discovered in the rock samples collected by the astronauts: armalcolite, tranquillityite, and pyroxferroite. Armalcolite |
was named after Armstrong, Aldrin, and Collins. All have subsequently been found on Earth. While on the surface, Armstrong uncovered a plaque mounted on the LM ladder, bearing two drawings of Earth (of the Western and Eastern Hemispheres), an inscription, and signatures of the astronauts and President Nixon. The inscription read: At the behest of the Nixon administration to add a reference to God, NASA included the vague date as a reason to include A.D., which stands for Anno Domini, "in the year of our Lord" (although it should have been placed before the year, not after). Mission Control used a coded phrase to warn Armstrong his metabolic rates were high, and that he should slow down. He was moving rapidly from task to task as time ran out. As metabolic rates remained generally lower than expected for both astronauts throughout the walk, Mission Control granted the astronauts a 15-minute extension. In a 2010 interview, Armstrong explained that NASA limited the first moonwalk's time and distance because there was no empirical proof of how much cooling water the astronauts' PLSS backpacks would consume to handle their body heat generation while working on the Moon. Lunar ascent Aldrin entered Eagle first. With some difficulty the astronauts lifted film and two sample boxes containing of lunar surface material to the LM hatch using a flat cable pulley device called the Lunar Equipment Conveyor (LEC). This proved to be an inefficient tool, and later missions preferred to carry equipment and samples up to the LM by hand. Armstrong reminded Aldrin of a bag of memorial items in his sleeve pocket, and Aldrin tossed the bag down. Armstrong then jumped onto the ladder's third rung, and climbed into the LM. After transferring to LM life support, the explorers lightened the ascent stage for the return to lunar orbit by tossing out their PLSS backpacks, lunar overshoes, an empty Hasselblad camera, and other equipment. The hatch was closed again at 05:11:13. They then pressurized the LM and settled down to sleep. Presidential speech writer William Safire had prepared an In Event of Moon Disaster announcement for Nixon to read in the event the Apollo 11 astronauts were stranded on the Moon. The remarks were in a memo from Safire to Nixon's White House Chief of Staff H. R. Haldeman, in which Safire suggested a protocol the administration might follow in reaction to such a disaster. |
According to the plan, Mission Control would "close down communications" with the LM, and a clergyman would "commend their souls to the deepest of the deep" in a public ritual likened to burial at sea. The last line of the prepared text contained an allusion to Rupert Brooke's World War I poem "The Soldier". While moving inside the cabin, Aldrin accidentally damaged the circuit breaker that would arm the main engine for liftoff from the Moon. There was a concern this would prevent firing the engine, stranding them on the Moon. The nonconductive tip of a Duro felt-tip pen was sufficient to activate the switch. After more than hours on the lunar surface, in addition to the scientific instruments, the astronauts left behind: an Apollo 1 mission patch in memory of astronauts Roger Chaffee, Gus Grissom, and Edward White, who died when their command module caught fire during a test in January 1967; two memorial medals of Soviet cosmonauts Vladimir Komarov and Yuri Gagarin, who died in 1967 and 1968 respectively; a memorial bag containing a gold replica of an olive branch as a traditional symbol of peace; and a silicon message disk carrying the goodwill statements by Presidents Eisenhower, Kennedy, Johnson, and Nixon along with messages from leaders of 73 countries around the world. The disk also carries a listing of the leadership of the US Congress, a listing of members of the four committees of the House and Senate responsible for the NASA legislation, and the names of NASA's past and then-current top management. After about seven hours of rest, the crew was awakened by Houston to prepare for the return flight. Two and a half hours later, at 17:54:00 UTC, they lifted off in Eagle ascent stage to rejoin Collins aboard Columbia in lunar orbit. Film taken from the LM ascent stage upon liftoff from the Moon reveals the American flag, planted some from the descent stage, whipping violently in the exhaust of the ascent stage engine. Aldrin looked up in time to witness the flag topple: "The ascent stage of the LM separated ... I was concentrating on the computers, and Neil was studying the attitude indicator, but I looked up long enough to see the flag fall over." Subsequent Apollo missions planted their flags farther from the LM. Columbia in lunar orbit During his day flying solo around the Moon, Collins never felt lonely. Although |
it has been said "not since Adam has any human known such solitude", Collins felt very much a part of the mission. In his autobiography he wrote: "this venture has been structured for three men, and I consider my third to be as necessary as either of the other two". In the 48 minutes of each orbit when he was out of radio contact with the Earth while Columbia passed round the far side of the Moon, the feeling he reported was not fear or loneliness, but rather "awareness, anticipation, satisfaction, confidence, almost exultation". One of Collins' first tasks was to identify the lunar module on the ground. To give Collins an idea where to look, Mission Control radioed that they believed the lunar module landed about off target. Each time he passed over the suspected lunar landing site, he tried in vain to find the module. On his first orbits on the back side of the Moon, Collins performed maintenance activities such as dumping excess water produced by the fuel cells and preparing the cabin for Armstrong and Aldrin to return. Just before he reached the dark side on the third orbit, Mission Control informed Collins there was a problem with the temperature of the coolant. If it became too cold, parts of Columbia might freeze. Mission Control advised him to assume manual control and implement Environmental Control System Malfunction Procedure 17. Instead, Collins flicked the switch on the system from automatic to manual and back to automatic again, and carried on with normal housekeeping chores, while keeping an eye on the temperature. When Columbia came back around to the near side of the Moon again, he was able to report that the problem had been resolved. For the next couple of orbits, he described his time on the back side of the Moon as "relaxing". After Aldrin and Armstrong completed their EVA, Collins slept so he could be rested for the rendezvous. While the flight plan called for Eagle to meet up with Columbia, Collins was prepared for a contingency in which he would fly Columbia down to meet Eagle. Return Eagle rendezvoused with Columbia at 21:24 UTC on July 21, and the two docked at 21:35. Eagles ascent stage was jettisoned into lunar orbit at 23:41. Just before the Apollo 12 flight, it was noted that Eagle was still likely to be orbiting the Moon. Later NASA |
reports mentioned that Eagle orbit had decayed, resulting in it impacting in an "uncertain location" on the lunar surface. In 2021, however, some calculations show that the lander may still be in orbit. On July 23, the last night before splashdown, the three astronauts made a television broadcast in which Collins commented: Aldrin added: Armstrong concluded: On the return to Earth, a bearing at the Guam tracking station failed, potentially preventing communication on the last segment of the Earth return. A regular repair was not possible in the available time but the station director, Charles Force, had his ten-year-old son Greg use his small hands to reach into the housing and pack it with grease. Greg was later thanked by Armstrong. Splashdown and quarantine The aircraft carrier , under the command of Captain Carl J. Seiberlich, was selected as the primary recovery ship (PRS) for Apollo 11 on June 5, replacing its sister ship, the LPH , which had recovered Apollo 10 on May 26. Hornet was then at her home port of Long Beach, California. On reaching Pearl Harbor on July 5, Hornet embarked the Sikorsky SH-3 Sea King helicopters of HS-4, a unit which specialized in recovery of Apollo spacecraft, specialized divers of UDT Detachment Apollo, a 35-man NASA recovery team, and about 120 media representatives. To make room, most of Hornets air wing was left behind in Long Beach. Special recovery equipment was also loaded, including a boilerplate command module used for training. On July 12, with Apollo 11 still on the launch pad, Hornet departed Pearl Harbor for the recovery area in the central Pacific, in the vicinity of . A presidential party consisting of Nixon, Borman, Secretary of State William P. Rogers and National Security Advisor Henry Kissinger flew to Johnston Atoll on Air Force One, then to the command ship USS Arlington in Marine One. After a night on board, they would fly to Hornet in Marine One for a few hours of ceremonies. On arrival aboard Hornet, the party was greeted by the Commander-in-Chief, Pacific Command (CINCPAC), Admiral John S. McCain Jr., and NASA Administrator Thomas O. Paine, who flew to Hornet from Pago Pago in one of Hornets carrier onboard delivery aircraft. Weather satellites were not yet common, but US Air Force Captain Hank Brandli had access to top-secret spy satellite images. He realized that a storm front was headed for the |
Apollo recovery area. Poor visibility which could make locating the capsule difficult, and strong upper-level winds which "would have ripped their parachutes to shreds" according to Brandli, posed a serious threat to the safety of the mission. Brandli alerted Navy Captain Willard S. Houston Jr., the commander of the Fleet Weather Center at Pearl Harbor, who had the required security clearance. On their recommendation, Rear Admiral Donald C. Davis, commander of Manned Spaceflight Recovery Forces, Pacific, advised NASA to change the recovery area, each man risking his career. A new location was selected northeast. This altered the flight plan. A different sequence of computer programs was used, one never before attempted. In a conventional entry, trajectory event P64 was followed by P67. For a skip-out re-entry, P65 and P66 were employed to handle the exit and entry parts of the skip. In this case, because they were extending the re-entry but not actually skipping out, P66 was not invoked and instead, P65 led directly to P67. The crew were also warned they would not be in a full-lift (heads-down) attitude when they entered P67. The first program's acceleration subjected the astronauts to ; the second, to . Before dawn on July 24, Hornet launched four Sea King helicopters and three Grumman E-1 Tracers. Two of the E-1s were designated as "air boss" while the third acted as a communications relay aircraft. Two of the Sea Kings carried divers and recovery equipment. The third carried photographic equipment, and the fourth carried the decontamination swimmer and the flight surgeon. At 16:44 UTC (05:44 local time) Columbias drogue parachutes were deployed. This was observed by the helicopters. Seven minutes later Columbia struck the water forcefully east of Wake Island, south of Johnston Atoll, and from Hornet, at . with seas and winds at from the east were reported under broken clouds at with visibility of at the recovery site. Reconnaissance aircraft flying to the original splashdown location reported the conditions Brandli and Houston had predicted. During splashdown, Columbia landed upside down but was righted within ten minutes by flotation bags activated by the astronauts. A diver from the Navy helicopter hovering above attached a sea anchor to prevent it from drifting. More divers attached flotation collars to stabilize the module and positioned rafts for astronaut extraction. The divers then passed biological isolation garments (BIGs) to the astronauts, and assisted them into the life |
raft. The possibility of bringing back pathogens from the lunar surface was considered remote, but NASA took precautions at the recovery site. The astronauts were rubbed down with a sodium hypochlorite solution and Columbia wiped with Povidone-iodine to remove any lunar dust that might be present. The astronauts were winched on board the recovery helicopter. BIGs were worn until they reached isolation facilities on board Hornet. The raft containing decontamination materials was intentionally sunk. After touchdown on Hornet at 17:53 UTC, the helicopter was lowered by the elevator into the hangar bay, where the astronauts walked the to the Mobile quarantine facility (MQF), where they would begin the Earth-based portion of their 21 days of quarantine. This practice would continue for two more Apollo missions, Apollo 12 and Apollo 14, before the Moon was proven to be barren of life, and the quarantine process dropped. Nixon welcomed the astronauts back to Earth. He told them: "[A]s a result of what you've done, the world has never been closer together before." After Nixon departed, Hornet was brought alongside the Columbia, which was lifted aboard by the ship's crane, placed on a dolly and moved next to the MQF. It was then attached to the MQF with a flexible tunnel, allowing the lunar samples, film, data tapes and other items to be removed. Hornet returned to Pearl Harbor, where the MQF was loaded onto a Lockheed C-141 Starlifter and airlifted to the Manned Spacecraft Center. The astronauts arrived at the Lunar Receiving Laboratory at 10:00 UTC on July 28. Columbia was taken to Ford Island for deactivation, and its pyrotechnics made safe. It was then taken to Hickham Air Force Base, from whence it was flown to Houston in a Douglas C-133 Cargomaster, reaching the Lunar Receiving Laboratory on July 30. In accordance with the Extra-Terrestrial Exposure Law, a set of regulations promulgated by NASA on July 16 to codify its quarantine protocol, the astronauts continued in quarantine. After three weeks in confinement (first in the Apollo spacecraft, then in their trailer on Hornet, and finally in the Lunar Receiving Laboratory), the astronauts were given a clean bill of health. On August 10, 1969, the Interagency Committee on Back Contamination met in Atlanta and lifted the quarantine on the astronauts, on those who had joined them in quarantine (NASA physician William Carpentier and MQF project engineer John Hirasaki), and on Columbia itself. |
Loose equipment from the spacecraft remained in isolation until the lunar samples were released for study. Celebrations On August 13, the three astronauts rode in ticker-tape parades in their honor in New York and Chicago, with an estimated six million attendees. On the same evening in Los Angeles there was an official state dinner to celebrate the flight, attended by members of Congress, 44 governors, Chief Justice of the United States Warren E. Burger and his predecessor, Earl Warren, and ambassadors from 83 nations at the Century Plaza Hotel. Nixon and Agnew honored each astronaut with a presentation of the Presidential Medal of Freedom. The three astronauts spoke before a joint session of Congress on September 16, 1969. They presented two US flags, one to the House of Representatives and the other to the Senate, that they had carried with them to the surface of the Moon. The flag of American Samoa on Apollo 11 is on display at the Jean P. Haydon Museum in Pago Pago, the capital of American Samoa. This celebration began a 38-day world tour that brought the astronauts to 22 foreign countries and included visits with the leaders of many countries. The crew toured from September 29 to November 5. Many nations honored the first human Moon landing with special features in magazines or by issuing Apollo 11 commemorative postage stamps or coins. Legacy Cultural significance Humans walking on the Moon and returning safely to Earth accomplished Kennedy's goal set eight years earlier. In Mission Control during the Apollo 11 landing, Kennedy's speech flashed on the screen, followed by the words "TASK ACCOMPLISHED, July 1969". The success of Apollo 11 demonstrated the United States' technological superiority; and with the success of Apollo 11, America had won the Space Race. New phrases permeated into the English language. "If they can send a man to the Moon, why can't they ...?" became a common saying following Apollo 11. Armstrong's words on the lunar surface also spun off various parodies. While most people celebrated the accomplishment, disenfranchised Americans saw it as a symbol of the divide in America, evidenced by protesters led by Ralph Abernathy outside of Kennedy Space Center the day before Apollo 11 launched. NASA Administrator Thomas Paine met with Abernathy at the occasion, both hoping that the space program can spur progress also in other regards, such as poverty in the US. Paine was then |
asked, and agreed, to host protesters as spectators at the launch, and Abernathy, awestruck by the spectacle, prayed for the astronauts. Racial and financial inequalities frustrated citizens who wondered why money spent on the Apollo program was not spent taking care of humans on Earth. A poem by Gil Scott-Heron called "Whitey on the Moon" (1970) illustrated the racial inequality in the United States that was highlighted by the Space Race. The poem starts with: Twenty percent of the world's population watched humans walk on the Moon for the first time. While Apollo 11 sparked the interest of the world, the follow-on Apollo missions did not hold the interest of the nation. One possible explanation was the shift in complexity. Landing someone on the Moon was an easy goal to understand; lunar geology was too abstract for the average person. Another is that Kennedy's goal of landing humans on the Moon had already been accomplished. A well-defined objective helped Project Apollo accomplish its goal, but after it was completed it was hard to justify continuing the lunar missions. While most Americans were proud of their nation's achievements in space exploration, only once during the late 1960s did the Gallup Poll indicate that a majority of Americans favored "doing more" in space as opposed to "doing less". By 1973, 59 percent of those polled favored cutting spending on space exploration. The Space Race had been won, and Cold War tensions were easing as the US and Soviet Union entered the era of détente. This was also a time when inflation was rising, which put pressure on the government to reduce spending. What saved the space program was that it was one of the few government programs that had achieved something great. Drastic cuts, warned Caspar Weinberger, the deputy director of the Office of Management and Budget, might send a signal that "our best years are behind us". After the Apollo 11 mission, officials from the Soviet Union said landing humans on the Moon was dangerous and unnecessary. At the time the Soviet Union was attempting to retrieve lunar samples robotically. The Soviets publicly denied there was a race to the Moon, and indicated they were not making an attempt. Mstislav Keldysh said in July 1969, "We are concentrating wholly on the creation of large satellite systems." It was revealed in 1989 that the Soviets had tried to send people to the |
Moon, but were unable due to technological difficulties. The public's reaction in the Soviet Union was mixed. The Soviet government limited the release of information about the lunar landing, which affected the reaction. A portion of the populace did not give it any attention, and another portion was angered by it. The Apollo 11 landing is referenced in the songs "Armstrong, Aldrin and Collins" by The Byrds on the 1969 album Ballad of Easy Rider and "Coon on the Moon" by Howlin' Wolf on the 1973 album The Back Door Wolf. Spacecraft The command module Columbia went on a tour of the United States, visiting 49 state capitals, the District of Columbia, and Anchorage, Alaska. In 1971, it was transferred to the Smithsonian Institution, and was displayed at the National Air and Space Museum (NASM) in Washington, DC. It was in the central Milestones of Flight exhibition hall in front of the Jefferson Drive entrance, sharing the main hall with other pioneering flight vehicles such as the Wright Flyer, Spirit of St. Louis, Bell X-1, North American X-15 and Friendship 7. Columbia was moved in 2017 to the NASM Mary Baker Engen Restoration Hangar at the Steven F. Udvar-Hazy Center in Chantilly, Virginia, to be readied for a four-city tour titled Destination Moon: The Apollo 11 Mission. This included Space Center Houston from October 14, 2017, to March 18, 2018, the Saint Louis Science Center from April 14 to September 3, 2018, the Senator John Heinz History Center in Pittsburgh from September 29, 2018, to February 18, 2019, and its last location at Museum of Flight in Seattle from March 16 to September 2, 2019. Continued renovations at the Smithsonian allowed time for an additional stop for the capsule, and it was moved to the Cincinnati Museum Center. The ribbon cutting ceremony was on September 29, 2019. For 40 years Armstrong's and Aldrin's space suits were displayed in the museum's Apollo to the Moon exhibit, until it permanently closed on December 3, 2018, to be replaced by a new gallery which was scheduled to open in 2022. A special display of Armstrong's suit was unveiled for the 50th anniversary of Apollo 11 in July 2019. The quarantine trailer, the flotation collar and the flotation bags are in the Smithsonian's Steven F. Udvar-Hazy Center annex near Washington Dulles International Airport in Chantilly, Virginia, where they are on display along with a |
test lunar module. The descent stage of the LM Eagle remains on the Moon. In 2009, the Lunar Reconnaissance Orbiter (LRO) imaged the various Apollo landing sites on the surface of the Moon, for the first time with sufficient resolution to see the descent stages of the lunar modules, scientific instruments, and foot trails made by the astronauts. The remains of the ascent stage lie at an unknown location on the lunar surface, after being abandoned and impacting the Moon. The location is uncertain because Eagle ascent stage was not tracked after it was jettisoned, and the lunar gravity field is sufficiently non-uniform to make the orbit of the spacecraft unpredictable after a short time. In March 2012 a team of specialists financed by Amazon founder Jeff Bezos located the F-1 engines from the S-IC stage that launched Apollo 11 into space. They were found on the Atlantic seabed using advanced sonar scanning. His team brought parts of two of the five engines to the surface. In July 2013, a conservator discovered a serial number under the rust on one of the engines raised from the Atlantic, which NASA confirmed was from Apollo 11. The S-IVB third stage which performed Apollo 11's trans-lunar injection remains in a solar orbit near to that of Earth. Moon rocks The main repository for the Apollo Moon rocks is the Lunar Sample Laboratory Facility at the Lyndon B. Johnson Space Center in Houston, Texas. For safekeeping, there is also a smaller collection stored at White Sands Test Facility near Las Cruces, New Mexico. Most of the rocks are stored in nitrogen to keep them free of moisture. They are handled only indirectly, using special tools. Over 100 research laboratories worldwide conduct studies of the samples; approximately 500 samples are prepared and sent to investigators every year. In November 1969, Nixon asked NASA to make up about 250 presentation Apollo 11 lunar sample displays for 135 nations, the fifty states of the United States and its possessions, and the United Nations. Each display included Moon dust from Apollo 11 and flags, including the one of the Soviet Union, taken along by Apollo 11. The rice-sized particles were four small pieces of Moon soil weighing about 50 mg and were enveloped in a clear acrylic button about as big as a United States half dollar coin. This acrylic button magnified the grains of lunar dust. Nixon |
gave the Apollo 11 lunar sample displays as goodwill gifts in 1970. Experiment results The Passive Seismic Experiment ran until the command uplink failed on August 25, 1969. The downlink failed on December 14, 1969. , the Lunar Laser Ranging experiment remains operational. Armstrong's camera Armstrong's Hasselblad camera was thought to be lost or left on the Moon surface. LM memorabilia In 2015, after Armstrong died in 2012, his widow contacted the National Air and Space Museum to inform them she had found a white cloth bag in one of Armstrong's closets. The bag contained various items, which should have been left behind in the lunar module, including the 16mm Data Acquisition Camera that had been used to capture images of the first Moon landing. The camera is currently on display at the National Air and Space Museum. Anniversary events 40th anniversary On July 15, 2009, Life.com released a photo gallery of previously unpublished photos of the astronauts taken by Life photographer Ralph Morse prior to the Apollo 11 launch. From July 16 to 24, 2009, NASA streamed the original mission audio on its website in real time 40 years to the minute after the events occurred. It is in the process of restoring the video footage and has released a preview of key moments. In July 2010, air-to-ground voice recordings and film footage shot in Mission Control during the Apollo 11 powered descent and landing was re-synchronized and released for the first time. The John F. Kennedy Presidential Library and Museum set up an Adobe Flash website that rebroadcasts the transmissions of Apollo 11 from launch to landing on the Moon. On July 20, 2009, Armstrong, Aldrin, and Collins met with US President Barack Obama at the White House. "We expect that there is, as we speak, another generation of kids out there who are looking up at the sky and are going to be the next Armstrong, Collins, and Aldrin", Obama said. "We want to make sure that NASA is going to be there for them when they want to take their journey." On August 7, 2009, an act of Congress awarded the three astronauts a Congressional Gold Medal, the highest civilian award in the United States. The bill was sponsored by Florida Senator Bill Nelson and Florida Representative Alan Grayson. A group of British scientists interviewed as part of the anniversary events reflected on the significance of |
the Moon landing: 50th anniversary On June 10, 2015, Congressman Bill Posey introduced resolution H.R. 2726 to the 114th session of the United States House of Representatives directing the United States Mint to design and sell commemorative coins in gold, silver and clad for the 50th anniversary of the Apollo 11 mission. On January 24, 2019, the Mint released the Apollo 11 Fiftieth Anniversary commemorative coins to the public on its website. A documentary film, Apollo 11, with restored footage of the 1969 event, premiered in IMAX on March 1, 2019, and broadly in theaters on March 8. The Smithsonian Institute's National Air and Space Museum and NASA sponsored the "Apollo 50 Festival" on the National Mall in Washington DC. The three day (July 18 to 20, 2019) outdoor festival featured hands-on exhibits and activities, live performances, and speakers such as Adam Savage and NASA scientists. As part of the festival, a projection of the tall Saturn V rocket was displayed on the east face of the tall Washington Monument from July 16 through the 20th from 9:30 pm until 11:30 pm (EDT). The program also included a 17-minute show that combined full-motion video projected on the Washington Monument to recreate the assembly and launch of the Saturn V rocket. The projection was joined by a wide recreation of the Kennedy Space Center countdown clock and two large video screens showing archival footage to recreate the time leading up to the moon landing. There were three shows per night on July 19–20, with the last show on Saturday, delayed slightly so the portion where Armstrong first set foot on the Moon would happen exactly 50 years to the second after the actual event. On July 19, 2019, the Google Doodle paid tribute to the Apollo 11 Moon Landing, complete with a link to an animated YouTube video with voiceover by astronaut Michael Collins. Aldrin, Collins, and Armstrong's sons were hosted by President Donald Trump in the Oval Office. Films and documentaries Footprints on the Moon, a 1969 documentary film by Bill Gibson and Barry Coe, about the Apollo 11 mission Moonwalk One, a 1971 documentary film by Theo Kamecke Apollo 11: As it Happened, a 1994 six-hour documentary on ABC News' coverage of the event Apollo 11, a 2019 documentary film by Todd Douglas Miller with restored footage of the 1969 event Chasing the Moon, a July 2019 PBS three-night |
six-hour documentary, directed by Robert Stone, examined the events leading up to the Apollo 11 mission. An accompanying book of the same name was also released. 8 Days: To the Moon and Back, a PBS and BBC Studios 2019 documentary film by Anthony Philipson re-enacting major portions of the Apollo 11 mission using mission audio recordings, new studio footage, NASA and news archives, and computer-generated imagery. See also Moon landing conspiracy theories References Notes Citations In some of the following sources, times are shown in the format hours:minutes:seconds (e.g. 109:24:15), referring to the mission's Ground Elapsed Time (GET), based on the official launch time of July 16, 1969, 13:32:00 UTC (000:00:00 GET). Sources External links "Apollo 11 transcripts" at Spacelog Apollo 11 in real time Multimedia —Remastered videos of the original landing. Dynamic timeline of lunar excursion. Lunar Reconnaissance Orbiter Camera Apollo 11 Restored EVA Part 1 (1h of restored footage) Apollo 11: As They Photographed It (Augmented Reality) The New York Times, Interactive, July 18, 2019 "Coverage of the Flight of Apollo 11" provided by Todd Kosovich for RadioTapes.com. Radio station recordings (airchecks) covering the flight of Apollo 11. Buzz Aldrin Neil Armstrong Michael Collins (astronaut) Apollo program missions 1969 on the Moon Soft landings on the Moon Spacecraft launched by Saturn rockets Articles containing video clips Crewed missions to the Moon |
Apollo 8 (December 21–27, 1968) was the first crewed spacecraft to leave low Earth orbit and the first human spaceflight to reach the Moon. The crew orbited the Moon ten times without landing, and then departed safely back to Earth. These three astronauts—Frank Borman, James Lovell, and William Anders—were the first humans to witness and photograph the far side of the Moon and an Earthrise. Apollo 8 launched on December 21, 1968, and was the second crewed spaceflight mission flown in the United States Apollo space program after Apollo7, which stayed in Earth orbit. Apollo8 was the third flight and the first crewed launch of the Saturn V rocket, and was the first human spaceflight from the Kennedy Space Center, located adjacent to Cape Kennedy Air Force Station in Florida. Originally planned as the second crewed Apollo Lunar Module and command module test, to be flown in an elliptical medium Earth orbit in early 1969, the mission profile was changed in August 1968 to a more ambitious command-module-only lunar orbital flight to be flown in December, as the lunar module was not yet ready to make its first flight. Astronaut Jim McDivitt's crew, who were training to fly the first lunar module flight in low Earth orbit, became the crew for the Apollo9 mission, and Borman's crew were moved to the Apollo8 mission. This left Borman's crew with two to three months' less training and preparation time than originally planned, and replaced the planned lunar module training with translunar navigation training. Apollo 8 took 68 hours to travel the distance to the Moon. The crew orbited the Moon ten times over the course of twenty hours, during which they made a Christmas Eve television broadcast in which they read the first ten verses from the Book of Genesis. At the time, the broadcast was the most watched TV program ever. Apollo8's successful mission paved the way for Apollo 10 and, with Apollo11 in July 1969, the fulfillment of U.S. president John F. Kennedy's goal of landing a man on the Moon before the end of the decade. The Apollo8 astronauts returned to Earth on December 27, 1968, when their spacecraft splashed down in the northern Pacific Ocean. The crew members were named Time magazine's "Men of the Year" for 1968 upon their return. It is the last Apollo mission for which all three crew members are still living. Background In |
the late 1950s and early 1960s, the United States was engaged in the Cold War, a geopolitical rivalry with the Soviet Union. On October 4, 1957, the Soviet Union launched Sputnik 1, the first artificial satellite. This unexpected success stoked fears and imaginations around the world. It not only demonstrated that the Soviet Union had the capability to deliver nuclear weapons over intercontinental distances, it challenged American claims of military, economic, and technological superiority. The launch precipitated the Sputnik crisis and triggered the Space Race. President John F. Kennedy believed that not only was it in the national interest of the United States to be superior to other nations, but that the perception of American power was at least as important as the actuality. It was therefore intolerable to him for the Soviet Union to be more advanced in the field of space exploration. He was determined that the United States should compete, and sought a challenge that maximized its chances of winning. The Soviet Union had heavier-lifting carrier rockets, which meant Kennedy needed to choose a goal that was beyond the capacity of the existing generation of rocketry, one where the US and Soviet Union would be starting from a position of equality—something spectacular, even if it could not be justified on military, economic, or scientific grounds. After consulting with his experts and advisors, he chose such a project: to land a man on the Moon and return him to the Earth. This project already had a name: Project Apollo. An early and crucial decision was the adoption of lunar orbit rendezvous, under which a specialized spacecraft would land on the lunar surface. The Apollo spacecraft therefore had three primary components: a command module (CM) with a cabin for the three astronauts, and the only part that would return to Earth; a service module (SM) to provide the command module with propulsion, electrical power, oxygen, and water; and a two-stage lunar module (LM), which comprised a descent stage for landing on the Moon and an ascent stage to return the astronauts to lunar orbit. This configuration could be launched by the Saturn V rocket that was then under development. Framework Prime crew The initial crew assignment of Frank Borman as Commander, Michael Collins as Command Module Pilot (CMP) and William Anders as Lunar Module Pilot (LMP) for the third crewed Apollo flight was officially announced on November 20, 1967. |
Collins was replaced by Jim Lovell in July 1968, after suffering a cervical disc herniation that required surgery to repair. This crew was unique among pre-Space Shuttle era missions in that the commander was not the most experienced member of the crew: Lovell had flown twice before, on Gemini VII and Gemini XII. This would also be the first case of a commander of a previous mission (Lovell, Gemini XII) flying as a non-commander. This was also the first mission to reunite crewmates from a previous mission (Lovell and Borman, Gemini VII). , all three Apollo 8 astronauts remain alive. Backup crew The backup crew assignment of Neil Armstrong as Commander, Lovell as CMP, and Buzz Aldrin as LMP for the third crewed Apollo flight was officially announced at the same time as the prime crew. When Lovell was reassigned to the prime crew, Aldrin was moved to CMP, and Fred Haise was brought in as backup LMP. Armstrong would later command Apollo11, with Aldrin as LMP and Collins as CMP. Haise served on the backup crew of Apollo11 as LMP and flew on Apollo13 as LMP. Support personnel During Projects Mercury and Gemini, each mission had a prime and a backup crew. For Apollo, a third crew of astronauts was added, known as the support crew. The support crew maintained the flight plan, checklists, and mission ground rules, and ensured that the prime and backup crews were apprised of any changes. The support crew developed procedures in the simulators, especially those for emergency situations, so that the prime and backup crews could practice and master them in their simulator training. For Apollo8, the support crew consisted of Ken Mattingly, Vance Brand, and Gerald Carr. The capsule communicator (CAPCOM) was an astronaut at the Mission Control Center in Houston, Texas, who was the only person who communicated directly with the flight crew. For Apollo8, the CAPCOMs were Michael Collins, Gerald Carr, Ken Mattingly, Neil Armstrong, Buzz Aldrin, Vance Brand, and Fred Haise. The mission control teams rotated in three shifts, each led by a flight director. The directors for Apollo8 were Clifford E. Charlesworth (Green team), Glynn Lunney (Black team), and Milton Windler (Maroon team). Mission insignia and callsign The triangular shape of the insignia refers to the shape of the Apollo CM. It shows a red figure8 looping around the Earth and Moon to reflect both the mission number |
and the circumlunar nature of the mission. On the bottom of the8 are the names of the three astronauts. The initial design of the insignia was developed by Jim Lovell, who reportedly sketched it while riding in the back seat of a T-38 flight from California to Houston shortly after learning of Apollo8's re-designation as a lunar-orbital mission. The crew wanted to name their spacecraft, but NASA did not allow it. The crew would have likely chosen Columbiad, the name of the giant cannon that launches a space vehicle in Jules Verne's 1865 novel From the Earth to the Moon. The Apollo11 CM was named Columbia in part for that reason. Preparations Mission schedule On September 20, 1967, NASA adopted a seven-step plan for Apollo missions, with the final step being a Moon landing. Apollo4 and Apollo6 were "A" missions, tests of the SaturnV launch vehicle using an uncrewed Block I production model of the command and service module (CSM) in Earth orbit. Apollo5 was a "B" mission, a test of the LM in Earth orbit. Apollo7, scheduled for October 1968, would be a "C" mission, a crewed Earth-orbit flight of the CSM. Further missions depended on the readiness of the LM. It had been decided as early as May 1967 that there would be at least four additional missions. Apollo8 was planned as the "D" mission, a test of the LM in a low Earth orbit in December 1968 by James McDivitt, David Scott, and Russell Schweickart, while Borman's crew would fly the "E" mission, a more rigorous LM test in an elliptical medium Earth orbit as Apollo9, in early 1969. The "F" Mission would test the CSM and LM in lunar orbit, and the "G" mission would be the finale, the Moon landing. Production of the LM fell behind schedule, and when Apollo8's LM-3 arrived at the Kennedy Space Center (KSC) in June 1968, more than a hundred significant defects were discovered, leading Bob Gilruth, the director of the Manned Spacecraft Center (MSC), and others to conclude that there was no prospect of LM-3 being ready to fly in 1968. Indeed, it was possible that delivery would slip to February or March 1969. Following the original seven-step plan would have meant delaying the "D" and subsequent missions, and endangering the program's goal of a lunar landing before the end of 1969. George Low, the Manager of the Apollo |
Spacecraft Program Office, proposed a solution in August 1968 to keep the program on track despite the LM delay. Since the next CSM (designated as "CSM-103") would be ready three months before LM-3, a CSM-only mission could be flown in December 1968. Instead of repeating the "C" mission flight of Apollo7, this CSM could be sent all the way to the Moon, with the possibility of entering a lunar orbit and returning to Earth. The new mission would also allow NASA to test lunar landing procedures that would otherwise have had to wait until Apollo10, the scheduled "F" mission. This also meant that the medium Earth orbit "E" mission could be dispensed with. The net result was that only the "D" mission had to be delayed, and the plan for lunar landing in mid-1969 could remain on timeline. On August 9, 1968, Low discussed the idea with Gilruth, Flight Director Chris Kraft, and the Director of Flight Crew Operations, Donald Slayton. They then flew to the Marshall Space Flight Center (MSFC) in Huntsville, Alabama, where they met with KSC Director Kurt Debus, Apollo Program Director Samuel C. Phillips, Rocco Petrone, and Wernher von Braun. Kraft considered the proposal feasible from a flight control standpoint; Debus and Petrone agreed that the next Saturn V, AS-503, could be made ready by December 1; and von Braun was confident the pogo oscillation problems that had afflicted Apollo6 had been fixed. Almost every senior manager at NASA agreed with this new mission, citing confidence in both the hardware and the personnel, along with the potential for a circumlunar flight providing a significant morale boost. The only person who needed some convincing was James E. Webb, the NASA administrator. Backed by the full support of his agency, Webb authorized the mission. Apollo8 was officially changed from a "D" mission to a "C-Prime" lunar-orbit mission. With the change in mission for Apollo 8, Slayton asked McDivitt if he still wanted to fly it. McDivitt turned it down; his crew had spent a great deal of time preparing to test the LM, and that was what he still wanted to do. Slayton then decided to swap the prime and backup crews of the Dand Emissions. This swap also meant a swap of spacecraft, requiring Borman's crew to use CSM-103, while McDivitt's crew would use CSM-104, since CM-104 could not be made ready by December. David Scott was |
not happy about giving up CM-103, the testing of which he had closely supervised, for CM-104, although the two were almost identical, and Anders was less than enthusiastic about being an LMP on a flight with no LM. Instead, in order that the spacecraft would have the correct weight and balance, Apollo8 would carry LM test article, a boilerplate model of LM-3. Added pressure on the Apollo program to make its 1969 landing goal was provided by the Soviet Union's Zond5 mission, which flew some living creatures, including Russian tortoises, in a cislunar loop around the Moon and returned them to Earth on September 21. There was speculation within NASA and the press that they might be preparing to launch cosmonauts on a similar circumlunar mission before the end of 1968. Compounding these concerns, American reconnaissance satellites observed a mockup N1 being rolled to the pad at Baikonur in November 1967, with more activity in 1968. The Apollo 8 crew, now living in the crew quarters at Kennedy Space Center, received a visit from Charles Lindbergh and his wife, Anne Morrow Lindbergh, the night before the launch. They talked about how, before his 1927 flight, Lindbergh had used a piece of string to measure the distance from New York City to Paris on a globe and from that calculated the fuel needed for the flight. The total he had carried was a tenth of the amount that the Saturn V would burn every second. The next day, the Lindberghs watched the launch of Apollo8 from a nearby dune. Saturn V redesign The Saturn V rocket used by Apollo8 was designated AS-503, or the "03rd" model of the SaturnV ("5") Rocket to be used in the Apollo-Saturn ("AS") program. When it was erected in the Vehicle Assembly Building on December 20, 1967, it was thought that the rocket would be used for an uncrewed Earth-orbit test flight carrying a boilerplate command and service module. Apollo6 had suffered several major problems during its April 1968 flight, including severe pogo oscillation during its first stage, two second-stage engine failures, and a third stage that failed to reignite in orbit. Without assurances that these problems had been rectified, NASA administrators could not justify risking a crewed mission until additional uncrewed test flights proved the Saturn V was ready. Teams from the MSFC went to work on the problems. Of primary concern was the pogo |
oscillation, which would not only hamper engine performance, but could exert significant g-forces on a crew. A task force of contractors, NASA agency representatives, and MSFC researchers concluded that the engines vibrated at a frequency similar to the frequency at which the spacecraft itself vibrated, causing a resonance effect that induced oscillations in the rocket. A system that used helium gas to absorb some of these vibrations was installed. Of equal importance was the failure of three engines during flight. Researchers quickly determined that a leaking hydrogen fuel line ruptured when exposed to vacuum, causing a loss of fuel pressure in engine two. When an automatic shutoff attempted to close the liquid hydrogen valve and shut down engine two, it had accidentally shut down engine three's liquid oxygen due to a miswired connection. As a result, engine three failed within one second of engine two's shutdown. Further investigation revealed the same problem for the third-stage engine—a faulty igniter line. The team modified the igniter lines and fuel conduits, hoping to avoid similar problems on future launches. The teams tested their solutions in August 1968 at the MSFC. A Saturn stage IC was equipped with shock-absorbing devices to demonstrate the team's solution to the problem of pogo oscillation, while a Saturn Stage II was retrofitted with modified fuel lines to demonstrate their resistance to leaks and ruptures in vacuum conditions. Once NASA administrators were convinced that the problems had been solved, they gave their approval for a crewed mission using AS-503. The Apollo 8 spacecraft was placed on top of the rocket on September 21, and the rocket made the slow journey to the launch pad atop one of NASA's two massive crawler-transporters on October9. Testing continued all through December until the day before launch, including various levels of readiness testing from December5 through 11. Final testing of modifications to address the problems of pogo oscillation, ruptured fuel lines, and bad igniter lines took place on December 18, three days before the scheduled launch. Mission Parameter summary As the first crewed spacecraft to orbit more than one celestial body, Apollo8's profile had two different sets of orbital parameters, separated by a translunar injection maneuver. Apollo lunar missions would begin with a nominal circular Earth parking orbit. Apollo8 was launched into an initial orbit with an apogee of and a perigee of , with an inclination of 32.51° to the Equator, and |
an orbital period of 88.19 minutes. Propellant venting increased the apogee by over the 2hours, 44 minutes, and 30 seconds spent in the parking orbit. This was followed by a trans-lunar injection (TLI) burn of the S-IVB third stage for 318 seconds, accelerating the command and service module and LM test article from an orbital velocity of to the injection velocity of which set a record for the highest speed, relative to Earth, that humans had ever traveled. This speed was slightly less than the Earth's escape velocity of , but put Apollo8 into an elongated elliptical Earth orbit, close enough to the Moon to be captured by the Moon's gravity. The standard lunar orbit for Apollo missions was planned as a nominal circular orbit above the Moon's surface. Initial lunar orbit insertion was an ellipse with a perilune of and an apolune of , at an inclination of 12° from the lunar equator. This was then circularized at , with an orbital period of 128.7 minutes. The effect of lunar mass concentrations ("mascons") on the orbit was found to be greater than initially predicted; over the course of the ten lunar orbits lasting twenty hours, the orbital distance was perturbated to . Apollo 8 achieved a maximum distance from Earth of . Launch and trans-lunar injection Apollo 8 was launched at 12:51:00 UTC (07:51:00 Eastern Standard Time) on December 21, 1968, using the Saturn V's three stages to achieve Earth orbit. The S-IC first stage landed in the Atlantic Ocean at , and the S-II second stage landed at . The S-IVB third stage injected the craft into Earth orbit and remained attached to perform the TLI burn that would put the spacecraft on a trajectory to the Moon. Once the vehicle reached Earth orbit, both the crew and Houston flight controllers spent the next 2hours and 38 minutes checking that the spacecraft was in proper working order and ready for TLI. The proper operation of the S-IVB third stage of the rocket was crucial, and in the last uncrewed test, it had failed to reignite for this burn. Collins was the first CAPCOM on duty, and at 2hours, 27 minutes and 22 seconds after launch he radioed, "Apollo8. You are Go for TLI." This communication meant that Mission Control had given official permission for Apollo8 to go to the Moon. The S-IVB engine ignited on time and performed |
the TLI burn perfectly. Over the next five minutes, the spacecraft's speed increased from . After the S-IVB had placed the mission on course for the Moon, the command and service modules (CSM), the remaining Apollo8 spacecraft, separated from it. The crew then rotated the spacecraft to take photographs of the spent stage and then practiced flying in formation with it. As the crew rotated the spacecraft, they had their first views of the Earth as they moved away from it—this marked the first time humans had viewed the whole Earth at once. Borman became worried that the S-IVB was staying too close to the CSM and suggested to Mission Control that the crew perform a separation maneuver. Mission Control first suggested pointing the spacecraft towards Earth and using the small reaction control system (RCS) thrusters on the service module (SM) to add to their velocity away from the Earth, but Borman did not want to lose sight of the S-IVB. After discussion, the crew and Mission Control decided to burn in the Earth direction to increase speed, but at instead. The time needed to prepare and perform the additional burn put the crew an hour behind their onboard tasks. Five hours after launch, Mission Control sent a command to the S-IVB to vent its remaining fuel, changing its trajectory. The S-IVB, with the test article attached, posed no further hazard to Apollo8, passing the orbit of the Moon and going into a solar orbit with an inclination of 23.47° from the Earth's equatorial plane, and an orbital period of 340.80 days. It became a derelict object, and will continue to orbit the Sun for many years, if not retrieved. The Apollo 8 crew were the first humans to pass through the Van Allen radiation belts, which extend up to from Earth. Scientists predicted that passing through the belts quickly at the spacecraft's high speed would cause a radiation dosage of no more than a chest X-ray, or 1milligray (mGy; during a year, the average human receives a dose of 2to 3mGy). To record the actual radiation dosages, each crew member wore a Personal Radiation Dosimeter that transmitted data to Earth, as well as three passive film dosimeters that showed the cumulative radiation experienced by the crew. By the end of the mission, the crew members experienced an average radiation dose of 1.6 mGy. Lunar trajectory Lovell's main job as |
Command Module Pilot was as navigator. Although Mission Control normally performed all the actual navigation calculations, it was necessary to have a crew member adept at navigation so that the crew could return to Earth in case communication with Mission Control was lost. Lovell navigated by star sightings using a sextant built into the spacecraft, measuring the angle between a star and the Earth's (or the Moon's) horizon. This task was made difficult by a large cloud of debris around the spacecraft, which made it hard to distinguish the stars. By seven hours into the mission, the crew was about 1hour and 40 minutes behind flight plan because of the problems in moving away from the S-IVB and Lovell's obscured star sightings. The crew placed the spacecraft into Passive Thermal Control (PTC), also called "barbecue roll", in which the spacecraft rotated about once per hour around its long axis to ensure even heat distribution across the surface of the spacecraft. In direct sunlight, parts of the spacecraft's outer surface could be heated to over , while the parts in shadow would be . These temperatures could cause the heat shield to crack and propellant lines to burst. Because it was impossible to get a perfect roll, the spacecraft swept out a cone as it rotated. The crew had to make minor adjustments every half hour as the cone pattern got larger and larger. The first mid-course correction came eleven hours into the flight. The crew had been awake for more than 16 hours. Before launch, NASA had decided at least one crew member should be awake at all times to deal with problems that might arise. Borman started the first sleep shift but found sleeping difficult because of the constant radio chatter and mechanical noises. Testing on the ground had shown that the service propulsion system (SPS) engine had a small chance of exploding when burned for long periods unless its combustion chamber was "coated" first by burning the engine for a short period. This first correction burn was only 2.4 seconds and added about velocity prograde (in the direction of travel). This change was less than the planned , because of a bubble of helium in the oxidizer lines, which caused unexpectedly low propellant pressure. The crew had to use the small RCS thrusters to make up the shortfall. Two later planned mid-course corrections were canceled because the Apollo8 |
trajectory was found to be perfect. About an hour after starting his sleep shift, Borman obtained permission from ground control to take a Seconal sleeping pill. The pill had little effect. Borman eventually fell asleep, and then awoke feeling ill. He vomited twice and had a bout of diarrhea; this left the spacecraft full of small globules of vomit and feces, which the crew cleaned up as well as they could. Borman initially did not want everyone to know about his medical problems, but Lovell and Anders wanted to inform Mission Control. The crew decided to use the Data Storage Equipment (DSE), which could tape voice recordings and telemetry and dump them to Mission Control at high speed. After recording a description of Borman's illness they asked Mission Control to check the recording, stating that they "would like an evaluation of the voice comments". The Apollo 8 crew and Mission Control medical personnel held a conference using an unoccupied second-floor control room (there were two identical control rooms in Houston, on the second and third floors, only one of which was used during a mission). The conference participants concluded that there was little to worry about and that Borman's illness was either a 24-hour flu, as Borman thought, or a reaction to the sleeping pill. Researchers now believe that he was suffering from space adaptation syndrome, which affects about a third of astronauts during their first day in space as their vestibular system adapts to weightlessness. Space adaptation syndrome had not occurred on previous spacecraft (Mercury and Gemini), because those astronauts could not move freely in the small cabins of those spacecraft. The increased cabin space in the Apollo command module afforded astronauts greater freedom of movement, contributing to symptoms of space sickness for Borman and, later, astronaut Rusty Schweickart during Apollo9. The cruise phase was a relatively uneventful part of the flight, except for the crew's checking that the spacecraft was in working order and that they were on course. During this time, NASA scheduled a television broadcast at 31 hours after launch. The Apollo8 crew used a camera that broadcast in black-and-white only, using a Vidicon tube. The camera had two lenses, a very wide-angle (160°) lens, and a telephoto (9°) lens. During this first broadcast, the crew gave a tour of the spacecraft and attempted to show how the Earth appeared from space. However, difficulties aiming the |
narrow-angle lens without the aid of a monitor to show what it was looking at made showing the Earth impossible. Additionally, without proper filters, the Earth image became saturated by any bright source. In the end, all the crew could show the people watching back on Earth was a bright blob. After broadcasting for 17 minutes, the rotation of the spacecraft took the high-gain antenna out of view of the receiving stations on Earth and they ended the transmission with Lovell wishing his mother a happy birthday. By this time, the crew had completely abandoned the planned sleep shifts. Lovell went to sleep hours into the flight – three-and-a-half hours before he had planned to. A short while later, Anders also went to sleep after taking a sleeping pill. The crew was unable to see the Moon for much of the outward cruise. Two factors made the Moon almost impossible to see from inside the spacecraft: three of the five windows fogging up due to out-gassed oils from the silicone sealant, and the attitude required for passive thermal control. It was not until the crew had gone behind the Moon that they would be able to see it for the first time. Apollo 8 made a second television broadcast at 55 hours into the flight. This time, the crew rigged up filters meant for the still cameras so they could acquire images of the Earth through the telephoto lens. Although difficult to aim, as they had to maneuver the entire spacecraft, the crew was able to broadcast back to Earth the first television pictures of the Earth. The crew spent the transmission describing the Earth, what was visible, and the colors they could see. The transmission lasted 23 minutes. Lunar sphere of influence At about 55 hours and 40 minutes into the flight, and 13 hours before entering lunar orbit, the crew of Apollo8 became the first humans to enter the gravitational sphere of influence of another celestial body. In other words, the effect of the Moon's gravitational force on Apollo8 became stronger than that of the Earth. At the time it happened, Apollo8 was from the Moon and had a speed of relative to the Moon. This historic moment was of little interest to the crew, since they were still calculating their trajectory with respect to the launch pad at Kennedy Space Center. They would continue to do so |
until they performed their last mid-course correction, switching to a reference frame based on ideal orientation for the second engine burn they would make in lunar orbit. The last major event before Lunar Orbit Insertion (LOI) was a second mid-course correction. It was in retrograde (against the direction of travel) and slowed the spacecraft down by , effectively reducing the closest distance at which the spacecraft would pass the Moon. At exactly 61 hours after launch, about from the Moon, the crew burned the RCS for 11 seconds. They would now pass from the lunar surface. At 64 hours into the flight, the crew began to prepare for Lunar Orbit Insertion1 (LOI-1). This maneuver had to be performed perfectly, and due to orbital mechanics had to be on the far side of the Moon, out of contact with the Earth. After Mission Control was polled for a "go/no go" decision, the crew was told at 68 hours that they were Go and "riding the best bird we can find". Lovell replied, "We'll see you on the other side", and for the first time in history, humans travelled behind the Moon and out of radio contact with the Earth. With ten minutes remaining before LOI-1, the crew began one last check of the spacecraft systems and made sure that every switch was in its correct position. At that time, they finally got their first glimpses of the Moon. They had been flying over the unlit side, and it was Lovell who saw the first shafts of sunlight obliquely illuminating the lunar surface. The LOI burn was only two minutes away, so the crew had little time to appreciate the view. Lunar orbit The SPS was ignited at 69 hours, 8minutes, and 16 seconds after launch and burned for 4minutes and 7seconds, placing the Apollo8 spacecraft in orbit around the Moon. The crew described the burn as being the longest four minutes of their lives. If the burn had not lasted exactly the correct amount of time, the spacecraft could have ended up in a highly elliptical lunar orbit or even been flung off into space. If it had lasted too long, they could have struck the Moon. After making sure the spacecraft was working, they finally had a chance to look at the Moon, which they would orbit for the next 20 hours. On Earth, Mission Control continued to wait. If |
the crew had not burned the engine, or the burn had not lasted the planned length of time, the crew would have appeared early from behind the Moon. Exactly at the calculated moment the signal was received from the spacecraft, indicating it was in a orbit around the Moon. After reporting on the status of the spacecraft, Lovell gave the first description of what the lunar surface looked like: Lovell continued to describe the terrain they were passing over. One of the crew's major tasks was reconnaissance of planned future landing sites on the Moon, especially one in Mare Tranquillitatis that was planned as the Apollo11 landing site. The launch time of Apollo8 had been chosen to give the best lighting conditions for examining the site. A film camera had been set up in one of the spacecraft windows to record one frame per second of the Moon below. Bill Anders spent much of the next 20 hours taking as many photographs as possible of targets of interest. By the end of the mission, the crew had taken over eight hundred 70 mm still photographs and of 16 mm movie film. Throughout the hour that the spacecraft was in contact with Earth, Borman kept asking how the data for the SPS looked. He wanted to make sure that the engine was working and could be used to return early to the Earth if necessary. He also asked that they receive a "go/no go" decision before they passed behind the Moon on each orbit. As they reappeared for their second pass in front of the Moon, the crew set up equipment to broadcast a view of the lunar surface. Anders described the craters that they were passing over. At the end of this second orbit, they performed an 11-second LOI-2 burn of the SPS to circularize the orbit to . Throughout the next two orbits, the crew continued to check the spacecraft and to observe and photograph the Moon. During the third pass, Borman read a small prayer for his church. He had been scheduled to participate in a service at St. Christopher's Episcopal Church near Seabrook, Texas, but due to the Apollo8 flight, he was unable to attend. A fellow parishioner and engineer at Mission Control, Rod Rose, suggested that Borman read the prayer, which could be recorded and then replayed during the service. Earthrise When the spacecraft came out |
from behind the Moon for its fourth pass across the front, the crew witnessed an "Earthrise" in person for the first time in human history. NASA's Lunar Orbiter 1 had taken the first picture of an Earthrise from the vicinity of the Moon, on August 23, 1966. Anders saw the Earth emerging from behind the lunar horizon and called in excitement to the others, taking a black-and-white photograph as he did so. Anders asked Lovell for color film and then took Earthrise, a now famous color photo, later picked by Life magazine as one of its hundred photos of the century. Due to the synchronous rotation of the Moon about the Earth, Earthrise is not generally visible from the lunar surface. This is because, as seen from any one place on the Moon's surface, Earth remains in approximately the same position in the lunar sky, either above or below the horizon. Earthrise is generally visible only while orbiting the Moon, and at selected surface locations near the Moon's limb, where libration carries the Earth slightly above and below the lunar horizon. Anders continued to take photographs while Lovell assumed control of the spacecraft so that Borman could rest. Despite the difficulty resting in the cramped and noisy spacecraft, Borman was able to sleep for two orbits, awakening periodically to ask questions about their status. Borman awoke fully when he started to hear his fellow crew members make mistakes. They were beginning to not understand questions and had to ask for the answers to be repeated. Borman realized that everyone was extremely tired from not having a good night's sleep in over three days. He ordered Anders and Lovell to get some sleep and that the rest of the flight plan regarding observing the Moon be scrubbed. Anders initially protested, saying that he was fine, but Borman would not be swayed. Anders finally agreed under the condition that Borman would set up the camera to continue to take automatic pictures of the Moon. Borman also remembered that there was a second television broadcast planned, and with so many people expected to be watching, he wanted the crew to be alert. For the next two orbits, Anders and Lovell slept while Borman sat at the helm. As they rounded the Moon for the ninth time, the astronauts began the second television transmission. Borman introduced the crew, followed by each man giving his |
impression of the lunar surface and what it was like to be orbiting the Moon. Borman described it as being "a vast, lonely, forbidding expanse of nothing". Then, after talking about what they were flying over, Anders said that the crew had a message for all those on Earth. Each man on board read a section from the Biblical creation story from the Book of Genesis. Borman finished the broadcast by wishing a Merry Christmas to everyone on Earth. His message appeared to sum up the feelings that all three crewmen had from their vantage point in lunar orbit. Borman said, "And from the crew of Apollo8, we close with good night, good luck, a Merry Christmas and God bless all of you—all of you on the good Earth." The only task left for the crew at this point was to perform the trans-Earth injection (TEI), which was scheduled for hours after the end of the television transmission. The TEI was the most critical burn of the flight, as any failure of the SPS to ignite would strand the crew in lunar orbit, with little hope of escape. As with the previous burn, the crew had to perform the maneuver above the far side of the Moon, out of contact with Earth. The burn occurred exactly on time. The spacecraft telemetry was reacquired as it re-emerged from behind the Moon at 89 hours, 28 minutes, and 39 seconds, the exact time calculated. When voice contact was regained, Lovell announced, "Please be informed, there is a Santa Claus", to which Ken Mattingly, the current CAPCOM, replied, "That's affirmative, you are the best ones to know." The spacecraft began its journey back to Earth on December 25, Christmas Day. Unplanned manual realignment Later, Lovell used some otherwise idle time to do some navigational sightings, maneuvering the module to view various stars by using the computer keyboard. He accidentally erased some of the computer's memory, which caused the inertial measurement unit (IMU) to contain data indicating that the module was in the same relative orientation it had been in before lift-off; the IMU then fired the thrusters to "correct" the module's attitude. Once the crew realized why the computer had changed the module's attitude, they realized that they would have to reenter data to tell the computer the module's actual orientation. It took Lovell ten minutes to figure out the right numbers, using |
the thrusters to get the stars Rigel and Sirius aligned, and another 15 minutes to enter the corrected data into the computer. Sixteen months later, during the Apollo13 mission, Lovell would have to perform a similar manual realignment under more critical conditions after the module's IMU had to be turned off to conserve energy. Cruise back to Earth and reentry The cruise back to Earth was mostly a time for the crew to relax and monitor the spacecraft. As long as the trajectory specialists had calculated everything correctly, the spacecraft would reenter Earth's atmosphere two-and-a-half days after TEI and splash down in the Pacific. On Christmas afternoon, the crew made their fifth television broadcast. This time, they gave a tour of the spacecraft, showing how an astronaut lived in space. When they finished broadcasting, they found a small present from Slayton in the food locker: a real turkey dinner with stuffing, in the same kind of pack given to the troops in Vietnam. Another Slayton surprise was a gift of three miniature bottles of brandy, which Borman ordered the crew to leave alone until after they landed. They remained unopened, even years after the flight. There were also small presents to the crew from their wives. The next day, at about 124 hours into the mission, the sixth and final TV transmission showed the mission's best video images of the Earth, during a four-minute broadcast. After two uneventful days, the crew prepared for reentry. The computer would control the reentry, and all the crew had to do was put the spacecraft in the correct attitude, with the blunt end forward. In the event of computer failure, Borman was ready to take over. Separation from the service module prepared the command module for reentry by exposing the heat shield and shedding unneeded mass. The service module would burn up in the atmosphere as planned. Six minutes before they hit the top of the atmosphere, the crew saw the Moon rising above the Earth's horizon, just as had been calculated by the trajectory specialists. As the module hit the thin outer atmosphere, the crew noticed that it was becoming hazy outside as glowing plasma formed around the spacecraft. The spacecraft started slowing down, and the deceleration peaked at . With the computer controlling the descent by changing the attitude of the spacecraft, Apollo8 rose briefly like a skipping stone before descending to |
the ocean. At , the drogue parachute deployed, stabilizing the spacecraft, followed at by the three main parachutes. The spacecraft splashdown position was officially reported as in the North Pacific Ocean, southwest of Hawaii at 15:51:42 UTC on December 27, 1968. When the spacecraft hit the water, the parachutes dragged it over and left it upside down, in what was termed Stable2 position. As they were buffeted by a swell, Borman was sick, waiting for the three flotation balloons to right the spacecraft. About six minutes after splashdown, the command module was righted into a normal apex-up (Stable 1) orientation by its inflatable bag uprighting system. The first frogman from aircraft carrier arrived 43 minutes after splashdown. Forty-five minutes later, the crew was safe on the flight deck of the Yorktown. Legacy Historical importance Apollo 8 came at the end of 1968, a year that had seen much upheaval in the United States and most of the world. Even though the year saw political assassinations, political unrest in the streets of Europe and America, and the Prague Spring, Time magazine chose the crew of Apollo8 as its Men of the Year for 1968, recognizing them as the people who most influenced events in the preceding year. They had been the first people ever to leave the gravitational influence of the Earth and orbit another celestial body. They had survived a mission that even the crew themselves had rated as having only a fifty-fifty chance of fully succeeding. The effect of Apollo8 was summed up in a telegram from a stranger, received by Borman after the mission, that stated simply, "Thank you Apollo8. You saved 1968." One of the most famous aspects of the flight was the Earthrise picture that the crew took as they came around for their fourth orbit of the Moon. This was the first time that humans had taken such a picture while actually behind the camera, and it has been credited as one of the inspirations of the first Earth Day in 1970. It was selected as the first of Life magazine's 100 Photographs That Changed the World. Apollo 11 astronaut Michael Collins said, "Eight's momentous historic significance was foremost"; while space historian Robert K. Poole saw Apollo8 as the most historically significant of all the Apollo missions. The mission was the most widely covered by the media since the first American orbital flight, Mercury-Atlas 6 |
by John Glenn, in 1962. There were 1,200 journalists covering the mission, with the BBC's coverage broadcast in 54 countries in 15 different languages. The Soviet newspaper Pravda featured a quote from Boris Nikolaevich Petrov, Chairman of the Soviet Interkosmos program, who described the flight as an "outstanding achievement of American space sciences and technology". It is estimated that a quarter of the people alive at the time saw—either live or delayed—the Christmas Eve transmission during the ninth orbit of the Moon. The Apollo8 broadcasts won an Emmy Award, the highest honor given by the Academy of Television Arts & Sciences. Madalyn Murray O'Hair, an atheist, later caused controversy by bringing a lawsuit against NASA over the reading from Genesis. O'Hair wanted the courts to ban American astronauts—who were all government employees—from public prayer in space. Though the case was rejected by the Supreme Court of the United States, apparently for lack of jurisdiction in outer space, it caused NASA to be skittish about the issue of religion throughout the rest of the Apollo program. Buzz Aldrin, on Apollo11, self-communicated Presbyterian Communion on the surface of the Moon after landing; he refrained from mentioning this publicly for several years and referred to it only obliquely at the time. In 1969, the United States Post Office Department issued a postage stamp (Scott catalogue #1371) commemorating the Apollo8 flight around the Moon. The stamp featured a detail of the famous photograph of the Earthrise over the Moon taken by Anders on Christmas Eve, and the words, "In the beginning God...", the first words of the book of Genesis. In January 1969, just 18 days after the crew's return to Earth, they appeared in the Super Bowl III pre-game show, reciting the Pledge of Allegiance, before the national anthem was performed by trumpeter Lloyd Geisler of the Washington National Symphony Orchestra. Spacecraft location In January 1970, the spacecraft was delivered to Osaka, Japan, for display in the U.S. pavilion at Expo '70. It is now displayed at the Chicago Museum of Science and Industry, along with a collection of personal items from the flight donated by Lovell and the space suit worn by Frank Borman. Jim Lovell's Apollo8 space suit is on public display in the Visitor Center at NASA's Glenn Research Center. Bill Anders's space suit is on display at the Science Museum in London, United Kingdom. In popular culture Apollo 8's |
historic mission has been depicted and referred to in several forms, both documentary and fiction. The various television transmissions and 16 mm footage shot by the crew of Apollo8 were compiled and released by NASA in the 1969 documentary Debrief: Apollo8, hosted by Burgess Meredith. In addition, Spacecraft Films released, in 2003, a three-disc DVD set containing all of NASA's TV and 16 mm film footage related to the mission, including all TV transmissions from space, training and launch footage, and motion pictures taken in flight. Other documentaries include "Race to the Moon" (2005) as part of season 18 of American Experience and In the Shadow of the Moon (2007). Apollo's Daring Mission aired on PBS' Nova in December 2018, marking the flight's 50th anniversary. Apollo 8 serves as character development in the 1995 film Apollo 13, in which Jim Lovell is motivated to walk on the Moon by his Apollo 8 experience and later disappointed to be so near the surface twice without walking on it. Parts of the mission are dramatized in the 1998 miniseries From the Earth to the Moon episode "1968". The S-IVB stage of Apollo8 was also portrayed as the location of an alien device in the 1970 UFO episode "Conflict". Apollo8's lunar orbit insertion was chronicled with actual recordings in the song "The Other Side", on the 2015 album The Race for Space, by the band Public Service Broadcasting. In the credits of the animated film Free Birds (2013) a newspaper front page about the Apollo 8 mission is doctored to read: "As one of the most turbulent, tragic years in American history drew to a close, millions around the world were watching and listening as the Apollo 8 astronauts – Frank Gobbler, Jim Snood, and Bill Wattles – became the first turkeys to orbit another world." A documentary film, First to the Moon: The Journey of Apollo 8 was released in 2018. The choral music piece Earthrise by Luke Byrne commemorates the mission. The piece was premièred on January 19, 2020, by Sydney Philharmonia Choirs at the Sydney Opera House. Notes References Bibliography External links "Apollo 8" at Encyclopedia Astronautica Article about the 40th anniversary of Apollo8 Multimedia Apollo 8: Go for TLI 1969 NASA film at the Internet Archive Debrief: Apollo 8 1969 NASA film at the Internet Archive "Apollo 07 and 08 16mm Onboard Film (1968)" raw footage taken from Apollos |
7and8 at the Internet Archive Apollo 8 Around the Moon and Back 2018 YouTube video Apollo 08 Crewed missions to the Moon Spacecraft launched in 1968 1968 in the United States Spacecraft which reentered in 1968 December 1968 events Spacecraft launched by Saturn rockets Jim Lovell William Anders Frank Borman |
An astronaut (from the Ancient Greek (), meaning 'star', and (), meaning 'sailor') is a person trained, equipped, and deployed by a human spaceflight program to serve as a commander or crew member aboard a spacecraft. Although generally reserved for professional space travelers, the term is sometimes applied to anyone who travels into space, including scientists, politicians, journalists, and tourists. "Astronaut" technically applies to all human space travelers regardless of nationality. However, astronauts fielded by Russia or the Soviet Union are typically known instead as cosmonauts (from the Russian "kosmos" (космос), meaning "space", also borrowed from Greek). Comparatively recent developments in crewed spaceflight made by China have led to the rise of the term taikonaut (from the Mandarin "tàikōng" (), meaning "space"), although its use is somewhat informal and its origin is unclear. In China, the People's Liberation Army Astronaut Corps astronauts and their foreign counterparts are all officially called hángtiānyuán (, meaning "heaven navigator" or literally "heaven-sailing staff"). Since 1961, 600 astronauts have flown in space. Until 2002, astronauts were sponsored and trained exclusively by governments, either by the military or by civilian space agencies. With the suborbital flight of the privately funded SpaceShipOne in 2004, a new category of astronaut was created: the commercial astronaut. Definition The criteria for what constitutes human spaceflight vary, with some focus on the point where the atmosphere becomes so thin that centrifugal force, rather than aerodynamic force, carries a significant portion of the weight of the flight object. The Fédération Aéronautique Internationale (FAI) Sporting Code for astronautics recognizes only flights that exceed the Kármán line, at an altitude of . In the United States, professional, military, and commercial astronauts who travel above an altitude of are awarded astronaut wings. , 552 people from 36 countries have reached or more in altitude, of whom 549 reached low Earth orbit or beyond. Of these, 24 people have traveled beyond low Earth orbit, either to lunar orbit, the lunar surface, or, in one case, a loop around the Moon. Three of the 24—Jim Lovell, John Young and Eugene Cernan—did so twice. , under the U.S. definition, 558 people qualify as having reached space, above altitude. Of eight X-15 pilots who exceeded in altitude, only one, Joseph A. Walker, exceeded 100 kilometers (about 62.1 miles) and he did it two times, becoming the first person in space twice. Space travelers have spent over 41,790 man-days (114.5 |
man-years) in space, including over 100 astronaut-days of spacewalks. , the man with the longest cumulative time in space is Gennady Padalka, who has spent 879 days in space. Peggy A. Whitson holds the record for the most time in space by a woman, 377 days. Terminology In 1959, when both the United States and Soviet Union were planning, but had yet to launch humans into space, NASA Administrator T. Keith Glennan and his Deputy Administrator, Hugh Dryden, discussed whether spacecraft crew members should be called astronauts or cosmonauts. Dryden preferred "cosmonaut", on the grounds that flights would occur in and to the broader cosmos, while the "astro" prefix suggested flight specifically to the stars. Most NASA Space Task Group members preferred "astronaut", which survived by common usage as the preferred American term. When the Soviet Union launched the first man into space, Yuri Gagarin in 1961, they chose a term which anglicizes to "cosmonaut". Astronaut A professional space traveler is called an astronaut. The first known use of the term "astronaut" in the modern sense was by Neil R. Jones in his 1930 short story "The Death's Head Meteor". The word itself had been known earlier; for example, in Percy Greg's 1880 book Across the Zodiac, "astronaut" referred to a spacecraft. In Les Navigateurs de l'infini (1925) by J.-H. Rosny aîné, the word astronautique (astronautics) was used. The word may have been inspired by "aeronaut", an older term for an air traveler first applied in 1784 to balloonists. An early use of "astronaut" in a non-fiction publication is Eric Frank Russell's poem "The Astronaut", appearing in the November 1934 Bulletin of the British Interplanetary Society. The first known formal use of the term astronautics in the scientific community was the establishment of the annual International Astronautical Congress in 1950, and the subsequent founding of the International Astronautical Federation the following year. NASA applies the term astronaut to any crew member aboard NASA spacecraft bound for Earth orbit or beyond. NASA also uses the term as a title for those selected to join its Astronaut Corps. The European Space Agency similarly uses the term astronaut for members of its Astronaut Corps. Cosmonaut By convention, an astronaut employed by the Russian Federal Space Agency (or its Soviet predecessor) is called a cosmonaut in English texts. The word is an Anglicization of kosmonavt ( ). Other countries of the former Eastern Bloc |
use variations of the Russian kosmonavt, such as the (although Polish also uses , and the two words are considered synonyms). Coinage of the term has been credited to Soviet aeronautics (or "cosmonautics") pioneer Mikhail Tikhonravov (1900–1974). The first cosmonaut was Soviet Air Force pilot Yuri Gagarin, also the first person in space. He was part of the first six Soviet citizens, with German Titov, Yevgeny Khrunov, Andriyan Nikolayev, Pavel Popovich, and Grigoriy Nelyubov, who were given the title of pilot-cosmonaut in January 1961. Valentina Tereshkova was the first female cosmonaut and the first and youngest woman to have flown in space with a solo mission on the Vostok 6 in 1963. On 14 March 1995, Norman Thagard became the first American to ride to space on board a Russian launch vehicle, and thus became the first "American cosmonaut". Taikonaut In Chinese, the term (, "cosmos navigating personnel") is used for astronauts and cosmonauts in general, while (, "navigating celestial-heaven personnel") is used for Chinese astronauts. Here, (, literally "heaven-navigating", or spaceflight) is strictly defined as the navigation of outer space within the local star system, i.e. Solar System. The phrase (, "spaceman") is often used in Hong Kong and Taiwan. The term taikonaut is used by some English-language news media organizations for professional space travelers from China. The word has featured in the Longman and Oxford English dictionaries, and the term became more common in 2003 when China sent its first astronaut Yang Liwei into space aboard the Shenzhou 5 spacecraft. This is the term used by Xinhua News Agency in the English version of the Chinese People's Daily since the advent of the Chinese space program. The origin of the term is unclear; as early as May 1998, Chiew Lee Yih () from Malaysia, used it in newsgroups. Parastronaut For its 2022 Astronaut Group, the European Space Agency envisioned recruiting an astronaut with a physical disability, a category they called "parastronauts", with the intention but not guarantee of spaceflight. The categories of disability considered for the program were individuals with lower limb deficiency (either through amputation or congenital), leg length difference, or a short stature (less than ). On 23 November 2022, John McFall was selected to be the first ESA parastronaut. Other terms With the rise of space tourism, NASA and the Russian Federal Space Agency agreed to use the term "spaceflight participant" to distinguish those space |
travelers from professional astronauts on missions coordinated by those two agencies. While no nation other than Russia (and previously the Soviet Union), the United States, and China have launched a crewed spacecraft, several other nations have sent people into space in cooperation with one of these countries, e.g. the Soviet-led Interkosmos program. Inspired partly by these missions, other synonyms for astronaut have entered occasional English usage. For example, the term spationaut () is sometimes used to describe French space travelers, from the Latin word for "space"; the Malay term (deriving from angkasa meaning 'space') was used to describe participants in the Angkasawan program (note its similarity with the Indonesian term antariksawan). Plans of the Indian Space Research Organisation to launch its crewed Gaganyaan spacecraft have spurred at times public discussion if another term than astronaut should be used for the crew members, suggesting vyomanaut (from the Sanskrit word / meaning 'sky' or 'space') or gagannaut (from the Sanskrit word for 'sky'). In Finland, the NASA astronaut Timothy Kopra, a Finnish American, has sometimes been referred to as , from the Finnish word . Across Germanic languages, "astronaut" is used in conjunction with locally derived words like German's Raumfahrer, Dutch's ruimtevaarder, Swedish's rymdfarare and Norwegian's romfarer. As of 2021 in the United States, astronaut status is conferred on a person depending on the authorizing agency: one who flies in a vehicle above for NASA or the military is considered an astronaut (with no qualifier) one who flies in a vehicle to the International Space Station in a mission coordinated by NASA and Roscosmos is a spaceflight participant one who flies above in a non-NASA vehicle as a crewmember and demonstrates activities during flight that are essential to public safety, or contribute to human space flight safety, is considered a commercial astronaut by the Federal Aviation Administration one who flies to the International Space Station as part of a "privately funded, dedicated commercial spaceflight on a commercial launch vehicle dedicated to the mission ... to conduct approved commercial and marketing activities on the space station (or in a commercial segment attached to the station)" is considered a private astronaut by NASA (as of 2020, nobody has yet qualified for this status) a generally-accepted but unofficial term for a paying non-crew passenger who flies a private non-NASA or military vehicles above is a space tourist (as of 2020, nobody has yet qualified for |
this status) On July 20, 2021, the FAA issued an order redefining the eligibility criteria to be an astronaut in response to the private suborbital spaceflights of Jeff Bezos and Richard Branson. The new criteria states that one must have "[d]emonstrated activities during flight that were essential to public safety, or contributed to human space flight safety" in order to qualify as an astronaut. This new definition excludes Bezos and Branson. Space travel milestones The first human in space was Soviet Yuri Gagarin, who was launched on 12 April 1961, aboard Vostok 1 and orbited around the Earth for 108 minutes. The first woman in space was Soviet Valentina Tereshkova, who launched on 16 June 1963, aboard Vostok 6 and orbited Earth for almost three days. Alan Shepard became the first American and second person in space on 5 May 1961, on a 15-minute sub-orbital flight aboard Freedom 7. The first American to orbit the Earth was John Glenn, aboard Friendship 7 on 20 February 1962. The first American woman in space was Sally Ride, during Space Shuttle Challenger's mission STS-7, on 18 June 1983. In 1992, Mae Jemison became the first African American woman to travel in space aboard STS-47. Cosmonaut Alexei Leonov was the first person to conduct an extravehicular activity (EVA), (commonly called a "spacewalk"), on 18 March 1965, on the Soviet Union's Voskhod 2 mission. This was followed two and a half months later by astronaut Ed White who made the first American EVA on NASA's Gemini 4 mission. The first crewed mission to orbit the Moon, Apollo 8, included American William Anders who was born in Hong Kong, making him the first Asian-born astronaut in 1968. The Soviet Union, through its Intercosmos program, allowed people from other "socialist" (i.e. Warsaw Pact and other Soviet-allied) countries to fly on its missions, with the notable exceptions of France and Austria participating in Soyuz TM-7 and Soyuz TM-13, respectively. An example is Czechoslovak Vladimír Remek, the first cosmonaut from a country other than the Soviet Union or the United States, who flew to space in 1978 on a Soyuz-U rocket. Rakesh Sharma became the first Indian citizen to travel to space. He was launched aboard Soyuz T-11, on 2 April 1984. On 23 July 1980, Pham Tuan of Vietnam became the first Asian in space when he flew aboard Soyuz 37. Also in 1980, Cuban Arnaldo Tamayo Méndez |
became the first person of Hispanic and black African descent to fly in space, and in 1983, Guion Bluford became the first African American to fly into space. In April 1985, Taylor Wang became the first ethnic Chinese person in space. The first person born in Africa to fly in space was Patrick Baudry (France), in 1985. In 1985, Saudi Arabian Prince Sultan Bin Salman Bin AbdulAziz Al-Saud became the first Arab Muslim astronaut in space. In 1988, Abdul Ahad Mohmand became the first Afghan to reach space, spending nine days aboard the Mir space station. With the increase of seats on the Space Shuttle, the U.S. began taking international astronauts. In 1983, Ulf Merbold of West Germany became the first non-US citizen to fly in a US spacecraft. In 1984, Marc Garneau became the first of eight Canadian astronauts to fly in space (through 2010). In 1985, Rodolfo Neri Vela became the first Mexican-born person in space. In 1991, Helen Sharman became the first Briton to fly in space. In 2002, Mark Shuttleworth became the first citizen of an African country to fly in space, as a paying spaceflight participant. In 2003, Ilan Ramon became the first Israeli to fly in space, although he died during a re-entry accident. On 15 October 2003, Yang Liwei became China's first astronaut on the Shenzhou 5 spacecraft. On 30 May 2020, Doug Hurley and Bob Behnken became the first astronauts to launch on a private crewed spacecraft, Crew Dragon. Age milestones The youngest person to reach space is Oliver Daemen, who was 18 years and 11 months old when he made a suborbital spaceflight on Blue Origin NS-16. Daemen, who was a commercial passenger aboard the New Shepard, broke the record of Soviet cosmonaut Gherman Titov, who was 25 years old when he flew Vostok 2. Titov remains the youngest human to reach orbit; he rounded the planet 17 times. Titov was also the first person to suffer space sickness and the first person to sleep in space, twice. The oldest person to reach space is William Shatner, who was 90 years old when he made a suborbital spaceflight on Blue Origin NS-18. The oldest person to reach orbit is John Glenn, one of the Mercury 7, who was 77 when he flew on STS-95. For greater detail on age records, see . Duration and distance milestones 438 days is the longest |
time spent in space, by Russian Valeri Polyakov. As of 2006, the most spaceflights by an individual astronaut is seven, a record held by both Jerry L. Ross and Franklin Chang-Diaz. The farthest distance from Earth an astronaut has traveled was , when Jim Lovell, Jack Swigert, and Fred Haise went around the Moon during the Apollo 13 emergency. Civilian and non-government milestones The first civilian in space was Valentina Tereshkova aboard Vostok 6 (she also became the first woman in space on that mission). Tereshkova was only honorarily inducted into the USSR's Air Force, which did not accept female pilots at that time. A month later, Joseph Albert Walker became the first American civilian in space when his X-15 Flight 90 crossed the line, qualifying him by the international definition of spaceflight. Walker had joined the US Army Air Force but was not a member during his flight. The first people in space who had never been a member of any country's armed forces were both Konstantin Feoktistov and Boris Yegorov aboard Voskhod 1. The first non-governmental space traveler was Byron K. Lichtenberg, a researcher from the Massachusetts Institute of Technology who flew on STS-9 in 1983. In December 1990, Toyohiro Akiyama became the first paying space traveler and the first journalist in space for Tokyo Broadcasting System, a visit to Mir as part of an estimated $12 million (USD) deal with a Japanese TV station, although at the time, the term used to refer to Akiyama was "Research Cosmonaut". Akiyama suffered severe space sickness during his mission, which affected his productivity. The first self-funded space tourist was Dennis Tito on board the Russian spacecraft Soyuz TM-3 on 28 April 2001. Self-funded travelers The first person to fly on an entirely privately funded mission was Mike Melvill, piloting SpaceShipOne flight 15P on a suborbital journey, although he was a test pilot employed by Scaled Composites and not an actual paying space tourist. Seven others have paid the Russian Space Agency to fly into space: Dennis Tito (American): 28 April – 6 May 2001 (ISS) Mark Shuttleworth (South African): 25 April – 5 May 2002 (ISS) Gregory Olsen (American): 1–11 October 2005 (ISS) Anousheh Ansari (Iranian / American): 18–29 September 2006 (ISS) Charles Simonyi (Hungarian / American): 7–21 April 2007 (ISS), 26 March – 8 April 2009 (ISS) Richard Garriott (British / American): 12–24 October 2008 (ISS) Guy Laliberté (Canadian): |
30 September 2009 – 11 October 2009 (ISS) Jared Isaacman (American): 15–18 September 2021 (Free Flier) Yusaku Maezawa (Japanese): 8 – 24 December 2021 (ISS) Training The first NASA astronauts were selected for training in 1959. Early in the space program, military jet test piloting and engineering training were often cited as prerequisites for selection as an astronaut at NASA, although neither John Glenn nor Scott Carpenter (of the Mercury Seven) had any university degree, in engineering or any other discipline at the time of their selection. Selection was initially limited to military pilots. The earliest astronauts for both the US and the USSR tended to be jet fighter pilots, and were often test pilots. Once selected, NASA astronauts go through twenty months of training in a variety of areas, including training for extravehicular activity in a facility such as NASA's Neutral Buoyancy Laboratory. Astronauts-in-training (astronaut candidates) may also experience short periods of weightlessness (microgravity) in an aircraft called the "Vomit Comet," the nickname given to a pair of modified KC-135s (retired in 2000 and 2004, respectively, and replaced in 2005 with a C-9) which perform parabolic flights. Astronauts are also required to accumulate a number of flight hours in high-performance jet aircraft. This is mostly done in T-38 jet aircraft out of Ellington Field, due to its proximity to the Johnson Space Center. Ellington Field is also where the Shuttle Training Aircraft is maintained and developed, although most flights of the aircraft are conducted from Edwards Air Force Base. Astronauts in training must learn how to control and fly the Space Shuttle and, it is vital that they are familiar with the International Space Station so they know what they must do when they get there. NASA candidacy requirements The candidate must be a citizen of the United States. The candidate must complete a master's degree in a STEM field, including engineering, biological science, physical science, computer science or mathematics. The candidate must have at least two years of related professional experience obtained after degree completion or at least 1,000 hours pilot-in-command time on jet aircraft. The candidate must be able to pass the NASA long-duration flight astronaut physical. The candidate must also have skills in leadership, teamwork and communications. The master's degree requirement can also be met by: Two years of work toward a doctoral program in a related science, technology, engineering or math field. A completed Doctor |
of Medicine or Doctor of Osteopathic Medicine degree. Completion of a nationally recognized test pilot school program. Mission Specialist Educator Applicants must have a bachelor's degree with teaching experience, including work at the kindergarten through twelfth grade level. An advanced degree, such as a master's degree or a doctoral degree, is not required, but is strongly desired. Mission Specialist Educators, or "Educator Astronauts", were first selected in 2004, and as of 2007, there are three NASA Educator astronauts: Joseph M. Acaba, Richard R. Arnold, and Dorothy Metcalf-Lindenburger. Barbara Morgan, selected as back-up teacher to Christa McAuliffe in 1985, is considered to be the first Educator astronaut by the media, but she trained as a mission specialist. The Educator Astronaut program is a successor to the Teacher in Space program from the 1980s. Health risks of space travel Astronauts are susceptible to a variety of health risks including decompression sickness, barotrauma, immunodeficiencies, loss of bone and muscle, loss of eyesight, orthostatic intolerance, sleep disturbances, and radiation injury. A variety of large scale medical studies are being conducted in space via the National Space Biomedical Research Institute (NSBRI) to address these issues. Prominent among these is the Advanced Diagnostic Ultrasound in Microgravity Study in which astronauts (including former ISS commanders Leroy Chiao and Gennady Padalka) perform ultrasound scans under the guidance of remote experts to diagnose and potentially treat hundreds of medical conditions in space. This study's techniques are now being applied to cover professional and Olympic sports injuries as well as ultrasound performed by non-expert operators in medical and high school students. It is anticipated that remote guided ultrasound will have application on Earth in emergency and rural care situations, where access to a trained physician is often rare. A 2006 Space Shuttle experiment found that Salmonella typhimurium, a bacterium that can cause food poisoning, became more virulent when cultivated in space. More recently, in 2017, bacteria were found to be more resistant to antibiotics and to thrive in the near-weightlessness of space. Microorganisms have been observed to survive the vacuum of outer space. On 31 December 2012, a NASA-supported study reported that human spaceflight may harm the brain and accelerate the onset of Alzheimer's disease. In October 2015, the NASA Office of Inspector General issued a health hazards report related to space exploration, including a human mission to Mars. Over the last decade, flight surgeons and scientists at NASA have |
seen a pattern of vision problems in astronauts on long-duration space missions. The syndrome, known as visual impairment intracranial pressure (VIIP), has been reported in nearly two-thirds of space explorers after long periods spent aboard the International Space Station (ISS). On 2 November 2017, scientists reported that significant changes in the position and structure of the brain have been found in astronauts who have taken trips in space, based on MRI studies. Astronauts who took longer space trips were associated with greater brain changes. Being in space can be physiologically deconditioning on the body. It can affect the otolith organs and adaptive capabilities of the central nervous system. Zero gravity and cosmic rays can cause many implications for astronauts. In October 2018, NASA-funded researchers found that lengthy journeys into outer space, including travel to the planet Mars, may substantially damage the gastrointestinal tissues of astronauts. The studies support earlier work that found such journeys could significantly damage the brains of astronauts, and age them prematurely. Researchers in 2018 reported, after detecting the presence on the International Space Station (ISS) of five Enterobacter bugandensis bacterial strains, none pathogenic to humans, that microorganisms on ISS should be carefully monitored to continue assuring a medically healthy environment for astronauts. A study by Russian scientists published in April 2019 stated that astronauts facing space radiation could face temporary hindrance of their memory centers. While this does not affect their intellectual capabilities, it temporarily hinders formation of new cells in brain's memory centers. The study conducted by Moscow Institute of Physics and Technology (MIPT) concluded this after they observed that mice exposed to neutron and gamma radiation did not impact the rodents' intellectual capabilities. A 2020 study conducted on the brains of eight male Russian cosmonauts after they returned from long stays aboard the International Space Station showed that long-duration spaceflight causes many physiological adaptions, including macro- and microstructural changes. While scientists still know little about the effects of spaceflight on brain structure, this study showed that space travel can lead to new motor skills (dexterity), but also slightly weaker vision, both of which could possibly be long lasting. It was the first study to provide clear evidence of sensorimotor neuroplasticity, which is the brain's ability to change through growth and reorganization. Food and drink An astronaut on the International Space Station requires about mass of food per meal each day (inclusive of about packaging |
mass per meal). Space Shuttle astronauts worked with nutritionists to select menus that appealed to their individual tastes. Five months before flight, menus were selected and analyzed for nutritional content by the shuttle dietician. Foods are tested to see how they will react in a reduced gravity environment. Caloric requirements are determined using a basal energy expenditure (BEE) formula. On Earth, the average American uses about of water every day. On board the ISS astronauts limit water use to only about per day. Insignia In Russia, cosmonauts are awarded Pilot-Cosmonaut of the Russian Federation upon completion of their missions, often accompanied with the award of Hero of the Russian Federation. This follows the practice established in the USSR where cosmonauts were usually awarded the title Hero of the Soviet Union. At NASA, those who complete astronaut candidate training receive a silver lapel pin. Once they have flown in space, they receive a gold pin. U.S. astronauts who also have active-duty military status receive a special qualification badge, known as the Astronaut Badge, after participation on a spaceflight. The United States Air Force also presents an Astronaut Badge to its pilots who exceed in altitude. Deaths , eighteen astronauts (fourteen men and four women) have died during four space flights. By nationality, thirteen were American, four were Russian (Soviet Union), and one was Israeli. , eleven people (all men) have died training for spaceflight: eight Americans and three Russians. Six of these were in crashes of training jet aircraft, one drowned during water recovery training, and four were due to fires in pure oxygen environments. Astronaut David Scott left a memorial consisting of a statuette titled Fallen Astronaut on the surface of the Moon during his 1971 Apollo 15 mission, along with a list of the names of eight of the astronauts and six cosmonauts known at the time to have died in service. The Space Mirror Memorial, which stands on the grounds of the Kennedy Space Center Visitor Complex, is maintained by the Astronauts Memorial Foundation and commemorates the lives of the men and women who have died during spaceflight and during training in the space programs of the United States. In addition to twenty NASA career astronauts, the memorial includes the names of an X-15 test pilot, a U.S. Air Force officer who died while training for a then-classified military space program, and a civilian spaceflight participant. See also |
Notes References External links NASA: How to become an astronaut 101 List of International partnership organizations Encyclopedia Astronautica: Phantom cosmonauts collectSPACE: Astronaut appearances calendar spacefacts Spacefacts.de Manned astronautics: facts and figures Astronaut Candidate Brochure online Science occupations 1959 introductions |
A Modest Proposal For preventing the Children of Poor People From being a Burthen to Their Parents or Country, and For making them Beneficial to the Publick, commonly referred to as A Modest Proposal, is a Juvenalian satirical essay written and published anonymously by Jonathan Swift in 1729. The essay suggests that the impoverished Irish might ease their economic troubles by selling their children as food to rich gentlemen and ladies. This satirical hyperbole mocked heartless attitudes towards the poor, predominantly Irish Catholic (i.e., "Papists") as well as British policy towards the Irish in general. In English writing, the phrase "a modest proposal" is now conventionally an allusion to this style of straight-faced satire. Synopsis Swift's essay is widely held to be one of the greatest examples of sustained irony in the history of the English language. Much of its shock value derives from the fact that the first portion of the essay describes the plight of starving beggars in Ireland, so that the reader is unprepared for the surprise of Swift's solution when he states: "A young healthy child well nursed, is, at a year old, a most delicious nourishing and wholesome food, whether stewed, roasted, baked, or boiled; and I make no doubt that it will equally serve in a fricassee, or a ragout." Swift goes to great lengths to support his argument, including a list of possible preparation styles for the children, and calculations showing the financial benefits of his suggestion. He uses methods of argument throughout his essay which lampoon the then-influential William Petty and the social engineering popular among followers of Francis Bacon. These lampoons include appealing to the authority of "a very knowing American of my acquaintance in London" and "the famous Psalmanazar, a native of the island Formosa" (who had already confessed to not being from Formosa in 1706). In the tradition of Roman satire, Swift introduces the reforms he is actually suggesting by paralipsis: Population solutions George Wittkowsky argued that Swift's main target in A Modest Proposal was not the conditions in Ireland, but rather the can-do spirit of the times that led people to devise a number of illogical schemes that would purportedly solve social and economic ills. Swift was especially attacking projects that tried to fix population and labour issues with a simple cure-all solution. A memorable example of these sorts of schemes "involved the idea of running the poor |
through a joint-stock company". In response, Swift's Modest Proposal was "a burlesque of projects concerning the poor" that were in vogue during the early 18th century. A Modest Proposal also targets the calculating way people perceived the poor in designing their projects. The pamphlet targets reformers who "regard people as commodities". In the piece, Swift adopts the "technique of a political arithmetician" to show the utter ridiculousness of trying to prove any proposal with dispassionate statistics. Critics differ about Swift's intentions in using this faux-mathematical philosophy. Edmund Wilson argues that statistically "the logic of the 'Modest proposal' can be compared with defence of crime (arrogated to Marx) in which he argues that crime takes care of the superfluous population". Wittkowsky counters that Swift's satiric use of statistical analysis is an effort to enhance his satire that "springs from a spirit of bitter mockery, not from the delight in calculations for their own sake". Rhetoric Author Charles K. Smith argues that Swift's rhetorical style persuades the reader to detest the speaker and pity the Irish. Swift's specific strategy is twofold, using a "trap" to create sympathy for the Irish and a dislike of the narrator who, in the span of one sentence, "details vividly and with rhetorical emphasis the grinding poverty" but feels emotion solely for members of his own class. Swift's use of gripping details of poverty and his narrator's cool approach towards them create "two opposing points of view" that "alienate the reader, perhaps unconsciously, from a narrator who can view with 'melancholy' detachment a subject that Swift has directed us, rhetorically, to see in a much less detached way." Swift has his proposer further degrade the Irish by using language ordinarily reserved for animals. Lewis argues that the speaker uses "the vocabulary of animal husbandry" to describe the Irish. Once the children have been commodified, Swift's rhetoric can easily turn "people into animals, then meat, and from meat, logically, into tonnage worth a price per pound". Swift uses the proposer's serious tone to highlight the absurdity of his proposal. In making his argument, the speaker uses the conventional, textbook-approved order of argument from Swift's time (which was derived from the Latin rhetorician Quintilian). The contrast between the "careful control against the almost inconceivable perversion of his scheme" and "the ridiculousness of the proposal" create a situation in which the reader has "to consider just what perverted values and |
assumptions would allow such a diligent, thoughtful, and conventional man to propose so perverse a plan". Influences Scholars have speculated about which earlier works Swift may have had in mind when he wrote A Modest Proposal. Tertullian's Apology James William Johnson argues that A Modest Proposal was largely influenced and inspired by Tertullian's Apology: a satirical attack against early Roman persecution of Christianity. Johnson believes that Swift saw major similarities between the two situations. Johnson notes Swift's obvious affinity for Tertullian and the bold stylistic and structural similarities between the works A Modest Proposal and Apology. In structure, Johnson points out the same central theme, that of cannibalism and the eating of babies as well as the same final argument, that "human depravity is such that men will attempt to justify their own cruelty by accusing their victims of being lower than human". Stylistically, Swift and Tertullian share the same command of sarcasm and language. In agreement with Johnson, Donald C. Baker points out the similarity between both authors' tones and use of irony. Baker notes the uncanny way that both authors imply an ironic "justification by ownership" over the subject of sacrificing children—Tertullian while attacking pagan parents, and Swift while attacking the English mistreatment of the Irish poor. Defoe's The Generous Projector It has also been argued that A Modest Proposal was, at least in part, a response to the 1728 essay The Generous Projector or, A Friendly Proposal to Prevent Murder and Other Enormous Abuses, By Erecting an Hospital for Foundlings and Bastard Children by Swift's rival Daniel Defoe. Mandeville's Modest Defence of Publick Stews Bernard Mandeville's Modest Defence of Publick Stews asked to introduce public and state controlled bordellos. The 1726 paper acknowledges women's interests and—while not being a completely satirical text—has also been discussed as an inspiration for Jonathan Swift's title. Mandeville had by 1705 already become famous for the Fable of The Bees and deliberations on private vices and public benefits. John Locke's First Treatise of Government John Locke commented: "Be it then as Sir Robert says, that Anciently, it was usual for Men to sell and Castrate their Children. Let it be, that they exposed them; Add to it, if you please, for this is still greater Power, that they begat them for their Tables to fat and eat them: If this proves a right to do so, we may, by the same Argument, |
justifie Adultery, Incest and Sodomy, for there are examples of these too, both Ancient and Modern; Sins, which I suppose, have the Principle Aggravation from this, that they cross the main intention of Nature, which willeth the increase of Mankind, and the continuation of the Species in the highest perfection, and the distinction of Families, with the Security of the Marriage Bed, as necessary thereunto". (First Treatise, sec. 59). Economic themes Robert Phiddian's article "Have you eaten yet? The Reader in A Modest Proposal" focuses on two aspects of A Modest Proposal: the voice of Swift and the voice of the Proposer. Phiddian stresses that a reader of the pamphlet must learn to distinguish between the satirical voice of Jonathan Swift and the apparent economic projections of the Proposer. He reminds readers that "there is a gap between the narrator's meaning and the text's, and that a moral-political argument is being carried out by means of parody". While Swift's proposal is obviously not a serious economic proposal, George Wittkowsky, author of "Swift's Modest Proposal: The Biography of an Early Georgian Pamphlet", argues that to understand the piece fully it is important to understand the economics of Swift's time. Wittowsky argues that not enough critics have taken the time to focus directly on the mercantilism and theories of labour in 18th-century England. "If one regards the Modest Proposal simply as a criticism of condition, about all one can say is that conditions were bad and that Swift's irony brilliantly underscored this fact". "People are the riches of a nation" At the start of a new industrial age in the 18th century, it was believed that "people are the riches of the nation", and there was a general faith in an economy that paid its workers low wages because high wages meant workers would work less. Furthermore, "in the mercantilist view no child was too young to go into industry". In those times, the "somewhat more humane attitudes of an earlier day had all but disappeared and the laborer had come to be regarded as a commodity". Louis A. Landa composed a conducive analysis when he noted that it would have been healthier for the Irish economy to more appropriately utilize their human assets by giving the people an opportunity to "become a source of wealth to the nation" or else they "must turn to begging and thievery". This opportunity may have |
included giving the farmers more coin to work for, diversifying their professions, or even consider enslaving their people to lower coin usage and build up financial stock in Ireland. Landa wrote that, "Swift is maintaining that the maxim—people are the riches of a nation—applies to Ireland only if Ireland is permitted slavery or cannibalism" Landa presents Swift's A Modest Proposal as a critique of the popular and unjustified maxim of mercantilism in the 18th century that "people are the riches of a nation". Swift presents the dire state of Ireland and shows that mere population itself, in Ireland's case, did not always mean greater wealth and economy. The uncontrolled maxim fails to take into account that a person who does not produce in an economic or political way makes a country poorer, not richer. Swift also recognises the implications of this fact in making mercantilist philosophy a paradox: the wealth of a country is based on the poverty of the majority of its citizens. Swift however, Landa argues, is not merely criticising economic maxims but also addressing the fact that England was denying Irish citizens their natural rights and dehumanising them by viewing them as a mere commodity. Public reaction Swift's essay created a backlash within the aristocratic community after its publication. The work was aimed at the aristocracy, and they responded in turn. Several members of society wrote to Swift regarding the work. Lord Bathurst's letter (12 February 1729–30) intimated that he certainly understood the message, and interpreted it as a work of comedy: Modern usage A Modest Proposal is included in many literature courses as an example of early modern western satire. It also serves as an introduction to the concept and use of argumentative language, lending itself to secondary and post-secondary essay courses. Outside of the realm of English studies, A Modest Proposal is included in many comparative and global literature and history courses, as well as those of numerous other disciplines in the arts, humanities, and even the social sciences. A Modest Video Game Proposal is the title of an open letter sent by activist/former attorney Jack Thompson on 10 October 2005. The 2012 horror film Butcher Boys, written by the original The Texas Chain Saw Massacre scribe Kim Henkel, is said to be an updating of Jonathan Swift's A Modest Proposal. Henkel imagined the descendants of folks who actually took Swift up on his proposal. |
The film opens with a quote from J. Swift. Notes References (subscription needed) External links A Modest Proposal (CELT) A Modest Proposal (Gutenberg) A Modest Proposal – Annotated text aligned to Common Core Standards A Modest Proposal BBC Radio 4 In Our Time with Melvyn Bragg 'A modest proposal For preventing the children of poor people From being a Burthen to their Parents or the Country, And for making them Beneficial to the publick. The Third Edition, Dublin, Printed: And Reprinted at London, for Weaver Bickerton, in Devereux-Court near the Middle-Temple, 1730. Essays by Jonathan Swift Satirical essays Pamphlets 18th-century essays Works published anonymously British satire 1729 in Great Britain Cannibalism in fiction 1729 books |
The alkali metals consist of the chemical elements lithium (Li), sodium (Na), potassium (K), rubidium (Rb), caesium (Cs), and francium (Fr). Together with hydrogen they constitute group 1, which lies in the s-block of the periodic table. All alkali metals have their outermost electron in an s-orbital: this shared electron configuration results in their having very similar characteristic properties. Indeed, the alkali metals provide the best example of group trends in properties in the periodic table, with elements exhibiting well-characterised homologous behaviour. This family of elements is also known as the lithium family after its leading element. The alkali metals are all shiny, soft, highly reactive metals at standard temperature and pressure and readily lose their outermost electron to form cations with charge +1. They can all be cut easily with a knife due to their softness, exposing a shiny surface that tarnishes rapidly in air due to oxidation by atmospheric moisture and oxygen (and in the case of lithium, nitrogen). Because of their high reactivity, they must be stored under oil to prevent reaction with air, and are found naturally only in salts and never as the free elements. Caesium, the fifth alkali metal, is the most reactive of all the metals. All the alkali metals react with water, with the heavier alkali metals reacting more vigorously than the lighter ones. All of the discovered alkali metals occur in nature as their compounds: in order of abundance, sodium is the most abundant, followed by potassium, lithium, rubidium, caesium, and finally francium, which is very rare due to its extremely high radioactivity; francium occurs only in minute traces in nature as an intermediate step in some obscure side branches of the natural decay chains. Experiments have been conducted to attempt the synthesis of ununennium (Uue), which is likely to be the next member of the group; none were successful. However, ununennium may not be an alkali metal due to relativistic effects, which are predicted to have a large influence on the chemical properties of superheavy elements; even if it does turn out to be an alkali metal, it is predicted to have some differences in physical and chemical properties from its lighter homologues. Most alkali metals have many different applications. One of the best-known applications of the pure elements is the use of rubidium and caesium in atomic clocks, of which caesium atomic clocks form the basis of the second. |
A common application of the compounds of sodium is the sodium-vapour lamp, which emits light very efficiently. Table salt, or sodium chloride, has been used since antiquity. Lithium finds use as a psychiatric medication and as an anode in lithium batteries. Sodium, potassium and lithium are essential elements, having major biological roles as electrolytes, and although the other alkali metals are not essential, they also have various effects on the body, both beneficial and harmful. History Sodium compounds have been known since ancient times; salt (sodium chloride) has been an important commodity in human activities, as testified by the English word salary, referring to salarium, money paid to Roman soldiers for the purchase of salt. While potash has been used since ancient times, it was not understood for most of its history to be a fundamentally different substance from sodium mineral salts. Georg Ernst Stahl obtained experimental evidence which led him to suggest the fundamental difference of sodium and potassium salts in 1702, and Henri-Louis Duhamel du Monceau was able to prove this difference in 1736. The exact chemical composition of potassium and sodium compounds, and the status as chemical element of potassium and sodium, was not known then, and thus Antoine Lavoisier did not include either alkali in his list of chemical elements in 1789. Pure potassium was first isolated in 1807 in England by Humphry Davy, who derived it from caustic potash (KOH, potassium hydroxide) by the use of electrolysis of the molten salt with the newly invented voltaic pile. Previous attempts at electrolysis of the aqueous salt were unsuccessful due to potassium's extreme reactivity. Potassium was the first metal that was isolated by electrolysis. Later that same year, Davy reported extraction of sodium from the similar substance caustic soda (NaOH, lye) by a similar technique, demonstrating the elements, and thus the salts, to be different. Petalite (Li Al Si4O10) was discovered in 1800 by the Brazilian chemist José Bonifácio de Andrada in a mine on the island of Utö, Sweden. However, it was not until 1817 that Johan August Arfwedson, then working in the laboratory of the chemist Jöns Jacob Berzelius, detected the presence of a new element while analysing petalite ore. This new element was noted by him to form compounds similar to those of sodium and potassium, though its carbonate and hydroxide were less soluble in water and more alkaline than the other alkali metals. |
Berzelius gave the unknown material the name "lithion/lithina", from the Greek word λιθoς (transliterated as lithos, meaning "stone"), to reflect its discovery in a solid mineral, as opposed to potassium, which had been discovered in plant ashes, and sodium, which was known partly for its high abundance in animal blood. He named the metal inside the material "lithium". Lithium, sodium, and potassium were part of the discovery of periodicity, as they are among a series of triads of elements in the same group that were noted by Johann Wolfgang Döbereiner in 1850 as having similar properties. Rubidium and caesium were the first elements to be discovered using the spectroscope, invented in 1859 by Robert Bunsen and Gustav Kirchhoff. The next year, they discovered caesium in the mineral water from Bad Dürkheim, Germany. Their discovery of rubidium came the following year in Heidelberg, Germany, finding it in the mineral lepidolite. The names of rubidium and caesium come from the most prominent lines in their emission spectra: a bright red line for rubidium (from the Latin word rubidus, meaning dark red or bright red), and a sky-blue line for caesium (derived from the Latin word caesius, meaning sky-blue). Around 1865 John Newlands produced a series of papers where he listed the elements in order of increasing atomic weight and similar physical and chemical properties that recurred at intervals of eight; he likened such periodicity to the octaves of music, where notes an octave apart have similar musical functions. His version put all the alkali metals then known (lithium to caesium), as well as copper, silver, and thallium (which show the +1 oxidation state characteristic of the alkali metals), together into a group. His table placed hydrogen with the halogens. After 1869, Dmitri Mendeleev proposed his periodic table placing lithium at the top of a group with sodium, potassium, rubidium, caesium, and thallium. Two years later, Mendeleev revised his table, placing hydrogen in group 1 above lithium, and also moving thallium to the boron group. In this 1871 version, copper, silver, and gold were placed twice, once as part of group IB, and once as part of a "group VIII" encompassing today's groups 8 to 11. After the introduction of the 18-column table, the group IB elements were moved to their current position in the d-block, while alkali metals were left in group IA. Later the group's name was changed to group 1 |
in 1988. The trivial name "alkali metals" comes from the fact that the hydroxides of the group 1 elements are all strong alkalis when dissolved in water. There were at least four erroneous and incomplete discoveries before Marguerite Perey of the Curie Institute in Paris, France discovered francium in 1939 by purifying a sample of actinium-227, which had been reported to have a decay energy of 220 keV. However, Perey noticed decay particles with an energy level below 80 keV. Perey thought this decay activity might have been caused by a previously unidentified decay product, one that was separated during purification, but emerged again out of the pure actinium-227. Various tests eliminated the possibility of the unknown element being thorium, radium, lead, bismuth, or thallium. The new product exhibited chemical properties of an alkali metal (such as coprecipitating with caesium salts), which led Perey to believe that it was element 87, caused by the alpha decay of actinium-227. Perey then attempted to determine the proportion of beta decay to alpha decay in actinium-227. Her first test put the alpha branching at 0.6%, a figure that she later revised to 1%. The next element below francium (eka-francium) in the periodic table would be ununennium (Uue), element 119. The synthesis of ununennium was first attempted in 1985 by bombarding a target of einsteinium-254 with calcium-48 ions at the superHILAC accelerator at Berkeley, California. No atoms were identified, leading to a limiting yield of 300 nb. + → * → no atoms It is highly unlikely that this reaction will be able to create any atoms of ununennium in the near future, given the extremely difficult task of making sufficient amounts of einsteinium-254, which is favoured for production of ultraheavy elements because of its large mass, relatively long half-life of 270 days, and availability in significant amounts of several micrograms, to make a large enough target to increase the sensitivity of the experiment to the required level; einsteinium has not been found in nature and has only been produced in laboratories, and in quantities smaller than those needed for effective synthesis of superheavy elements. However, given that ununennium is only the first period 8 element on the extended periodic table, it may well be discovered in the near future through other reactions, and indeed an attempt to synthesise it is currently ongoing in Japan. Currently, none of the period 8 elements has been |
discovered yet, and it is also possible, due to drip instabilities, that only the lower period 8 elements, up to around element 128, are physically possible. No attempts at synthesis have been made for any heavier alkali metals: due to their extremely high atomic number, they would require new, more powerful methods and technology to make. Occurrence In the Solar System The Oddo–Harkins rule holds that elements with even atomic numbers are more common that those with odd atomic numbers, with the exception of hydrogen. This rule argues that elements with odd atomic numbers have one unpaired proton and are more likely to capture another, thus increasing their atomic number. In elements with even atomic numbers, protons are paired, with each member of the pair offsetting the spin of the other, enhancing stability. All the alkali metals have odd atomic numbers and they are not as common as the elements with even atomic numbers adjacent to them (the noble gases and the alkaline earth metals) in the Solar System. The heavier alkali metals are also less abundant than the lighter ones as the alkali metals from rubidium onward can only be synthesised in supernovae and not in stellar nucleosynthesis. Lithium is also much less abundant than sodium and potassium as it is poorly synthesised in both Big Bang nucleosynthesis and in stars: the Big Bang could only produce trace quantities of lithium, beryllium and boron due to the absence of a stable nucleus with 5 or 8 nucleons, and stellar nucleosynthesis could only pass this bottleneck by the triple-alpha process, fusing three helium nuclei to form carbon, and skipping over those three elements. On Earth The Earth formed from the same cloud of matter that formed the Sun, but the planets acquired different compositions during the formation and evolution of the solar system. In turn, the natural history of the Earth caused parts of this planet to have differing concentrations of the elements. The mass of the Earth is approximately 5.98 kg. It is composed mostly of iron (32.1%), oxygen (30.1%), silicon (15.1%), magnesium (13.9%), sulfur (2.9%), nickel (1.8%), calcium (1.5%), and aluminium (1.4%); with the remaining 1.2% consisting of trace amounts of other elements. Due to planetary differentiation, the core region is believed to be primarily composed of iron (88.8%), with smaller amounts of nickel (5.8%), sulfur (4.5%), and less than 1% trace elements. The alkali metals, due to |
their high reactivity, do not occur naturally in pure form in nature. They are lithophiles and therefore remain close to the Earth's surface because they combine readily with oxygen and so associate strongly with silica, forming relatively low-density minerals that do not sink down into the Earth's core. Potassium, rubidium and caesium are also incompatible elements due to their large ionic radii. Sodium and potassium are very abundant in earth, both being among the ten most common elements in Earth's crust; sodium makes up approximately 2.6% of the Earth's crust measured by weight, making it the sixth most abundant element overall and the most abundant alkali metal. Potassium makes up approximately 1.5% of the Earth's crust and is the seventh most abundant element. Sodium is found in many different minerals, of which the most common is ordinary salt (sodium chloride), which occurs in vast quantities dissolved in seawater. Other solid deposits include halite, amphibole, cryolite, nitratine, and zeolite. Many of these solid deposits occur as a result of ancient seas evaporating, which still occurs now in places such as Utah's Great Salt Lake and the Dead Sea. Despite their near-equal abundance in Earth's crust, sodium is far more common than potassium in the ocean, both because potassium's larger size makes its salts less soluble, and because potassium is bound by silicates in soil and what potassium leaches is absorbed far more readily by plant life than sodium. Despite its chemical similarity, lithium typically does not occur together with sodium or potassium due to its smaller size. Due to its relatively low reactivity, it can be found in seawater in large amounts; it is estimated that seawater is approximately 0.14 to 0.25 parts per million (ppm) or 25 micromolar. Its diagonal relationship with magnesium often allows it to replace magnesium in ferromagnesium minerals, where its crustal concentration is about 18 ppm, comparable to that of gallium and niobium. Commercially, the most important lithium mineral is spodumene, which occurs in large deposits worldwide. Rubidium is approximately as abundant as zinc and more abundant than copper. It occurs naturally in the minerals leucite, pollucite, carnallite, zinnwaldite, and lepidolite, although none of these contain only rubidium and no other alkali metals. Caesium is more abundant than some commonly known elements, such as antimony, cadmium, tin, and tungsten, but is much less abundant than rubidium. Francium-223, the only naturally occurring isotope of francium, is the |
product of the alpha decay of actinium-227 and can be found in trace amounts in uranium minerals. In a given sample of uranium, there is estimated to be only one francium atom for every 1018 uranium atoms. It has been calculated that there are at most 30 grams of francium in the earth's crust at any time, due to its extremely short half-life of 22 minutes. Properties Physical and chemical The physical and chemical properties of the alkali metals can be readily explained by their having an ns1 valence electron configuration, which results in weak metallic bonding. Hence, all the alkali metals are soft and have low densities, melting and boiling points, as well as heats of sublimation, vaporisation, and dissociation. They all crystallise in the body-centered cubic crystal structure, and have distinctive flame colours because their outer s electron is very easily excited. The ns1 configuration also results in the alkali metals having very large atomic and ionic radii, as well as very high thermal and electrical conductivity. Their chemistry is dominated by the loss of their lone valence electron in the outermost s-orbital to form the +1 oxidation state, due to the ease of ionising this electron and the very high second ionisation energy. Most of the chemistry has been observed only for the first five members of the group. The chemistry of francium is not well established due to its extreme radioactivity; thus, the presentation of its properties here is limited. What little is known about francium shows that it is very close in behaviour to caesium, as expected. The physical properties of francium are even sketchier because the bulk element has never been observed; hence any data that may be found in the literature are certainly speculative extrapolations. The alkali metals are more similar to each other than the elements in any other group are to each other. Indeed, the similarity is so great that it is quite difficult to separate potassium, rubidium, and caesium, due to their similar ionic radii; lithium and sodium are more distinct. For instance, when moving down the table, all known alkali metals show increasing atomic radius, decreasing electronegativity, increasing reactivity, and decreasing melting and boiling points as well as heats of fusion and vaporisation. In general, their densities increase when moving down the table, with the exception that potassium is less dense than sodium. One of the very few properties |
of the alkali metals that does not display a very smooth trend is their reduction potentials: lithium's value is anomalous, being more negative than the others. This is because the Li+ ion has a very high hydration energy in the gas phase: though the lithium ion disrupts the structure of water significantly, causing a higher change in entropy, this high hydration energy is enough to make the reduction potentials indicate it as being the most electropositive alkali metal, despite the difficulty of ionising it in the gas phase. The stable alkali metals are all silver-coloured metals except for caesium, which has a pale golden tint: it is one of only three metals that are clearly coloured (the other two being copper and gold). Additionally, the heavy alkaline earth metals calcium, strontium, and barium, as well as the divalent lanthanides europium and ytterbium, are pale yellow, though the colour is much less prominent than it is for caesium. Their lustre tarnishes rapidly in air due to oxidation. They all crystallise in the body-centered cubic crystal structure, and have distinctive flame colours because their outer s electron is very easily excited. Indeed, these flame test colours are the most common way of identifying them since all their salts with common ions are soluble. All the alkali metals are highly reactive and are never found in elemental forms in nature. Because of this, they are usually stored in mineral oil or kerosene (paraffin oil). They react aggressively with the halogens to form the alkali metal halides, which are white ionic crystalline compounds that are all soluble in water except lithium fluoride (Li F). The alkali metals also react with water to form strongly alkaline hydroxides and thus should be handled with great care. The heavier alkali metals react more vigorously than the lighter ones; for example, when dropped into water, caesium produces a larger explosion than potassium if the same number of moles of each metal is used. The alkali metals have the lowest first ionisation energies in their respective periods of the periodic table because of their low effective nuclear charge and the ability to attain a noble gas configuration by losing just one electron. Not only do the alkali metals react with water, but also with proton donors like alcohols and phenols, gaseous ammonia, and alkynes, the last demonstrating the phenomenal degree of their reactivity. Their great power as reducing agents |
makes them very useful in liberating other metals from their oxides or halides. The second ionisation energy of all of the alkali metals is very high as it is in a full shell that is also closer to the nucleus; thus, they almost always lose a single electron, forming cations. The alkalides are an exception: they are unstable compounds which contain alkali metals in a −1 oxidation state, which is very unusual as before the discovery of the alkalides, the alkali metals were not expected to be able to form anions and were thought to be able to appear in salts only as cations. The alkalide anions have filled s-subshells, which gives them enough stability to exist. All the stable alkali metals except lithium are known to be able to form alkalides, and the alkalides have much theoretical interest due to their unusual stoichiometry and low ionisation potentials. Alkalides are chemically similar to the electrides, which are salts with trapped electrons acting as anions. A particularly striking example of an alkalide is "inverse sodium hydride", H+Na− (both ions being complexed), as opposed to the usual sodium hydride, Na+H−: it is unstable in isolation, due to its high energy resulting from the displacement of two electrons from hydrogen to sodium, although several derivatives are predicted to be metastable or stable. In aqueous solution, the alkali metal ions form aqua ions of the formula [M(H2O)n]+, where n is the solvation number. Their coordination numbers and shapes agree well with those expected from their ionic radii. In aqueous solution the water molecules directly attached to the metal ion are said to belong to the first coordination sphere, also known as the first, or primary, solvation shell. The bond between a water molecule and the metal ion is a dative covalent bond, with the oxygen atom donating both electrons to the bond. Each coordinated water molecule may be attached by hydrogen bonds to other water molecules. The latter are said to reside in the second coordination sphere. However, for the alkali metal cations, the second coordination sphere is not well-defined as the +1 charge on the cation is not high enough to polarise the water molecules in the primary solvation shell enough for them to form strong hydrogen bonds with those in the second coordination sphere, producing a more stable entity. The solvation number for Li+ has been experimentally determined to be 4, forming |
the tetrahedral [Li(H2O)4]+: while solvation numbers of 3 to 6 have been found for lithium aqua ions, solvation numbers less than 4 may be the result of the formation of contact ion pairs, and the higher solvation numbers may be interpreted in terms of water molecules that approach [Li(H2O)4]+ through a face of the tetrahedron, though molecular dynamic simulations may indicate the existence of an octahedral hexaaqua ion. There are also probably six water molecules in the primary solvation sphere of the sodium ion, forming the octahedral [Na(H2O)6]+ ion. While it was previously thought that the heavier alkali metals also formed octahedral hexaaqua ions, it has since been found that potassium and rubidium probably form the [K(H2O)8]+ and [Rb(H2O)8]+ ions, which have the square antiprismatic structure, and that caesium forms the 12-coordinate [Cs(H2O)12]+ ion. Lithium The chemistry of lithium shows several differences from that of the rest of the group as the small Li+ cation polarises anions and gives its compounds a more covalent character. Lithium and magnesium have a diagonal relationship due to their similar atomic radii, so that they show some similarities. For example, lithium forms a stable nitride, a property common among all the alkaline earth metals (magnesium's group) but unique among the alkali metals. In addition, among their respective groups, only lithium and magnesium form organometallic compounds with significant covalent character (e.g. LiMe and MgMe2). Lithium fluoride is the only alkali metal halide that is poorly soluble in water, and lithium hydroxide is the only alkali metal hydroxide that is not deliquescent. Conversely, lithium perchlorate and other lithium salts with large anions that cannot be polarised are much more stable than the analogous compounds of the other alkali metals, probably because Li+ has a high solvation energy. This effect also means that most simple lithium salts are commonly encountered in hydrated form, because the anhydrous forms are extremely hygroscopic: this allows salts like lithium chloride and lithium bromide to be used in dehumidifiers and air-conditioners. Francium Francium is also predicted to show some differences due to its high atomic weight, causing its electrons to travel at considerable fractions of the speed of light and thus making relativistic effects more prominent. In contrast to the trend of decreasing electronegativities and ionisation energies of the alkali metals, francium's electronegativity and ionisation energy are predicted to be higher than caesium's due to the relativistic stabilisation of the 7s electrons; |
also, its atomic radius is expected to be abnormally low. Thus, contrary to expectation, caesium is the most reactive of the alkali metals, not francium. All known physical properties of francium also deviate from the clear trends going from lithium to caesium, such as the first ionisation energy, electron affinity, and anion polarisability, though due to the paucity of known data about francium many sources give extrapolated values, ignoring that relativistic effects make the trend from lithium to caesium become inapplicable at francium. Some of the few properties of francium that have been predicted taking relativity into account are the electron affinity (47.2 kJ/mol) and the enthalpy of dissociation of the Fr2 molecule (42.1 kJ/mol). The CsFr molecule is polarised as Cs+Fr−, showing that the 7s subshell of francium is much more strongly affected by relativistic effects than the 6s subshell of caesium. Additionally, francium superoxide (FrO2) is expected to have significant covalent character, unlike the other alkali metal superoxides, because of bonding contributions from the 6p electrons of francium. Nuclear All the alkali metals have odd atomic numbers; hence, their isotopes must be either odd–odd (both proton and neutron number are odd) or odd–even (proton number is odd, but neutron number is even). Odd–odd nuclei have even mass numbers, whereas odd–even nuclei have odd mass numbers. Odd–odd primordial nuclides are rare because most odd–odd nuclei are highly unstable with respect to beta decay, because the decay products are even–even, and are therefore more strongly bound, due to nuclear pairing effects. Due to the great rarity of odd–odd nuclei, almost all the primordial isotopes of the alkali metals are odd–even (the exceptions being the light stable isotope lithium-6 and the long-lived radioisotope potassium-40). For a given odd mass number, there can be only a single beta-stable nuclide, since there is not a difference in binding energy between even–odd and odd–even comparable to that between even–even and odd–odd, leaving other nuclides of the same mass number (isobars) free to beta decay toward the lowest-mass nuclide. An effect of the instability of an odd number of either type of nucleons is that odd-numbered elements, such as the alkali metals, tend to have fewer stable isotopes than even-numbered elements. Of the 26 monoisotopic elements that have only a single stable isotope, all but one have an odd atomic number and all but one also have an even number of neutrons. Beryllium is the |
single exception to both rules, due to its low atomic number. All of the alkali metals except lithium and caesium have at least one naturally occurring radioisotope: sodium-22 and sodium-24 are trace radioisotopes produced cosmogenically, potassium-40 and rubidium-87 have very long half-lives and thus occur naturally, and all isotopes of francium are radioactive. Caesium was also thought to be radioactive in the early 20th century, although it has no naturally occurring radioisotopes. (Francium had not been discovered yet at that time.) The natural long-lived radioisotope of potassium, potassium-40, makes up about 0.012% of natural potassium, and thus natural potassium is weakly radioactive. This natural radioactivity became a basis for a mistaken claim of the discovery for element 87 (the next alkali metal after caesium) in 1925. Natural rubidium is similarly slightly radioactive, with 27.83% being the long-lived radioisotope rubidium-87. Caesium-137, with a half-life of 30.17 years, is one of the two principal medium-lived fission products, along with strontium-90, which are responsible for most of the radioactivity of spent nuclear fuel after several years of cooling, up to several hundred years after use. It constitutes most of the radioactivity still left from the Chernobyl accident. Caesium-137 undergoes high-energy beta decay and eventually becomes stable barium-137. It is a strong emitter of gamma radiation. Caesium-137 has a very low rate of neutron capture and cannot be feasibly disposed of in this way, but must be allowed to decay. Caesium-137 has been used as a tracer in hydrologic studies, analogous to the use of tritium. Small amounts of caesium-134 and caesium-137 were released into the environment during nearly all nuclear weapon tests and some nuclear accidents, most notably the Goiânia accident and the Chernobyl disaster. As of 2005, caesium-137 is the principal source of radiation in the zone of alienation around the Chernobyl nuclear power plant. Its chemical properties as one of the alkali metals make it one of most problematic of the short-to-medium-lifetime fission products because it easily moves and spreads in nature due to the high water solubility of its salts, and is taken up by the body, which mistakes it for its essential congeners sodium and potassium. Periodic trends The alkali metals are more similar to each other than the elements in any other group are to each other. For instance, when moving down the table, all known alkali metals show increasing atomic radius, decreasing electronegativity, increasing reactivity, and decreasing |
melting and boiling points as well as heats of fusion and vaporisation. In general, their densities increase when moving down the table, with the exception that potassium is less dense than sodium. Atomic and ionic radii The atomic radii of the alkali metals increase going down the group. Because of the shielding effect, when an atom has more than one electron shell, each electron feels electric repulsion from the other electrons as well as electric attraction from the nucleus. In the alkali metals, the outermost electron only feels a net charge of +1, as some of the nuclear charge (which is equal to the atomic number) is cancelled by the inner electrons; the number of inner electrons of an alkali metal is always one less than the nuclear charge. Therefore, the only factor which affects the atomic radius of the alkali metals is the number of electron shells. Since this number increases down the group, the atomic radius must also increase down the group. The ionic radii of the alkali metals are much smaller than their atomic radii. This is because the outermost electron of the alkali metals is in a different electron shell than the inner electrons, and thus when it is removed the resulting atom has one fewer electron shell and is smaller. Additionally, the effective nuclear charge has increased, and thus the electrons are attracted more strongly towards the nucleus and the ionic radius decreases. First ionisation energy The first ionisation energy of an element or molecule is the energy required to move the most loosely held electron from one mole of gaseous atoms of the element or molecules to form one mole of gaseous ions with electric charge +1. The factors affecting the first ionisation energy are the nuclear charge, the amount of shielding by the inner electrons and the distance from the most loosely held electron from the nucleus, which is always an outer electron in main group elements. The first two factors change the effective nuclear charge the most loosely held electron feels. Since the outermost electron of alkali metals always feels the same effective nuclear charge (+1), the only factor which affects the first ionisation energy is the distance from the outermost electron to the nucleus. Since this distance increases down the group, the outermost electron feels less attraction from the nucleus and thus the first ionisation energy decreases. (This trend is broken |
in francium due to the relativistic stabilisation and contraction of the 7s orbital, bringing francium's valence electron closer to the nucleus than would be expected from non-relativistic calculations. This makes francium's outermost electron feel more attraction from the nucleus, increasing its first ionisation energy slightly beyond that of caesium.) The second ionisation energy of the alkali metals is much higher than the first as the second-most loosely held electron is part of a fully filled electron shell and is thus difficult to remove. Reactivity The reactivities of the alkali metals increase going down the group. This is the result of a combination of two factors: the first ionisation energies and atomisation energies of the alkali metals. Because the first ionisation energy of the alkali metals decreases down the group, it is easier for the outermost electron to be removed from the atom and participate in chemical reactions, thus increasing reactivity down the group. The atomisation energy measures the strength of the metallic bond of an element, which falls down the group as the atoms increase in radius and thus the metallic bond must increase in length, making the delocalised electrons further away from the attraction of the nuclei of the heavier alkali metals. Adding the atomisation and first ionisation energies gives a quantity closely related to (but not equal to) the activation energy of the reaction of an alkali metal with another substance. This quantity decreases going down the group, and so does the activation energy; thus, chemical reactions can occur faster and the reactivity increases down the group. Electronegativity Electronegativity is a chemical property that describes the tendency of an atom or a functional group to attract electrons (or electron density) towards itself. If the bond between sodium and chlorine in sodium chloride were covalent, the pair of shared electrons would be attracted to the chlorine because the effective nuclear charge on the outer electrons is +7 in chlorine but is only +1 in sodium. The electron pair is attracted so close to the chlorine atom that they are practically transferred to the chlorine atom (an ionic bond). However, if the sodium atom was replaced by a lithium atom, the electrons will not be attracted as close to the chlorine atom as before because the lithium atom is smaller, making the electron pair more strongly attracted to the closer effective nuclear charge from lithium. Hence, the larger alkali metal |
atoms (further down the group) will be less electronegative as the bonding pair is less strongly attracted towards them. As mentioned previously, francium is expected to be an exception. Because of the higher electronegativity of lithium, some of its compounds have a more covalent character. For example, lithium iodide (Li I) will dissolve in organic solvents, a property of most covalent compounds. Lithium fluoride (LiF) is the only alkali halide that is not soluble in water, and lithium hydroxide (LiOH) is the only alkali metal hydroxide that is not deliquescent. Melting and boiling points The melting point of a substance is the point where it changes state from solid to liquid while the boiling point of a substance (in liquid state) is the point where the vapour pressure of the liquid equals the environmental pressure surrounding the liquid and all the liquid changes state to gas. As a metal is heated to its melting point, the metallic bonds keeping the atoms in place weaken so that the atoms can move around, and the metallic bonds eventually break completely at the metal's boiling point. Therefore, the falling melting and boiling points of the alkali metals indicate that the strength of the metallic bonds of the alkali metals decreases down the group. This is because metal atoms are held together by the electromagnetic attraction from the positive ions to the delocalised electrons. As the atoms increase in size going down the group (because their atomic radius increases), the nuclei of the ions move further away from the delocalised electrons and hence the metallic bond becomes weaker so that the metal can more easily melt and boil, thus lowering the melting and boiling points. (The increased nuclear charge is not a relevant factor due to the shielding effect.) Density The alkali metals all have the same crystal structure (body-centred cubic) and thus the only relevant factors are the number of atoms that can fit into a certain volume and the mass of one of the atoms, since density is defined as mass per unit volume. The first factor depends on the volume of the atom and thus the atomic radius, which increases going down the group; thus, the volume of an alkali metal atom increases going down the group. The mass of an alkali metal atom also increases going down the group. Thus, the trend for the densities of the alkali metals depends |
on their atomic weights and atomic radii; if figures for these two factors are known, the ratios between the densities of the alkali metals can then be calculated. The resultant trend is that the densities of the alkali metals increase down the table, with an exception at potassium. Due to having the lowest atomic weight and the largest atomic radius of all the elements in their periods, the alkali metals are the least dense metals in the periodic table. Lithium, sodium, and potassium are the only three metals in the periodic table that are less dense than water: in fact, lithium is the least dense known solid at room temperature. Compounds The alkali metals form complete series of compounds with all usually encountered anions, which well illustrate group trends. These compounds can be described as involving the alkali metals losing electrons to acceptor species and forming monopositive ions. This description is most accurate for alkali halides and becomes less and less accurate as cationic and anionic charge increase, and as the anion becomes larger and more polarisable. For instance, ionic bonding gives way to metallic bonding along the series NaCl, Na2O, Na2S, Na3P, Na3As, Na3Sb, Na3Bi, Na. Hydroxides All the alkali metals react vigorously or explosively with cold water, producing an aqueous solution of a strongly basic alkali metal hydroxide and releasing hydrogen gas. This reaction becomes more vigorous going down the group: lithium reacts steadily with effervescence, but sodium and potassium can ignite, and rubidium and caesium sink in water and generate hydrogen gas so rapidly that shock waves form in the water that may shatter glass containers. When an alkali metal is dropped into water, it produces an explosion, of which there are two separate stages. The metal reacts with the water first, breaking the hydrogen bonds in the water and producing hydrogen gas; this takes place faster for the more reactive heavier alkali metals. Second, the heat generated by the first part of the reaction often ignites the hydrogen gas, causing it to burn explosively into the surrounding air. This secondary hydrogen gas explosion produces the visible flame above the bowl of water, lake or other body of water, not the initial reaction of the metal with water (which tends to happen mostly under water). The alkali metal hydroxides are the most basic known hydroxides. Recent research has suggested that the explosive behavior of alkali metals in |
water is driven by a Coulomb explosion rather than solely by rapid generation of hydrogen itself. All alkali metals melt as a part of the reaction with water. Water molecules ionise the bare metallic surface of the liquid metal, leaving a positively charged metal surface and negatively charged water ions. The attraction between the charged metal and water ions will rapidly increase the surface area, causing an exponential increase of ionisation. When the repulsive forces within the liquid metal surface exceeds the forces of the surface tension, it vigorously explodes. The hydroxides themselves are the most basic hydroxides known, reacting with acids to give salts and with alcohols to give oligomeric alkoxides. They easily react with carbon dioxide to form carbonates or bicarbonates, or with hydrogen sulfide to form sulfides or bisulfides, and may be used to separate thiols from petroleum. They react with amphoteric oxides: for example, the oxides of aluminium, zinc, tin, and lead react with the alkali metal hydroxides to give aluminates, zincates, stannates, and plumbates. Silicon dioxide is acidic, and thus the alkali metal hydroxides can also attack silicate glass. Intermetallic compounds The alkali metals form many intermetallic compounds with each other and the elements from groups 2 to 13 in the periodic table of varying stoichiometries, such as the sodium amalgams with mercury, including Na5Hg8 and Na3Hg. Some of these have ionic characteristics: taking the alloys with gold, the most electronegative of metals, as an example, NaAu and KAu are metallic, but RbAu and CsAu are semiconductors. NaK is an alloy of sodium and potassium that is very useful because it is liquid at room temperature, although precautions must be taken due to its extreme reactivity towards water and air. The eutectic mixture melts at −12.6 °C. An alloy of 41% caesium, 47% sodium, and 12% potassium has the lowest known melting point of any metal or alloy, −78 °C. Compounds with the group 13 elements The intermetallic compounds of the alkali metals with the heavier group 13 elements (aluminium, gallium, indium, and thallium), such as NaTl, are poor conductors or semiconductors, unlike the normal alloys with the preceding elements, implying that the alkali metal involved has lost an electron to the Zintl anions involved. Nevertheless, while the elements in group 14 and beyond tend to form discrete anionic clusters, group 13 elements tend to form polymeric ions with the alkali metal cations located between |
the giant ionic lattice. For example, NaTl consists of a polymeric anion (—Tl−—)n with a covalent diamond cubic structure with Na+ ions located between the anionic lattice. The larger alkali metals cannot fit similarly into an anionic lattice and tend to force the heavier group 13 elements to form anionic clusters. Boron is a special case, being the only nonmetal in group 13. The alkali metal borides tend to be boron-rich, involving appreciable boron–boron bonding involving deltahedral structures, and are thermally unstable due to the alkali metals having a very high vapour pressure at elevated temperatures. This makes direct synthesis problematic because the alkali metals do not react with boron below 700 °C, and thus this must be accomplished in sealed containers with the alkali metal in excess. Furthermore, exceptionally in this group, reactivity with boron decreases down the group: lithium reacts completely at 700 °C, but sodium at 900 °C and potassium not until 1200 °C, and the reaction is instantaneous for lithium but takes hours for potassium. Rubidium and caesium borides have not even been characterised. Various phases are known, such as LiB10, NaB6, NaB15, and KB6. Under high pressure the boron–boron bonding in the lithium borides changes from following Wade's rules to forming Zintl anions like the rest of group 13. Compounds with the group 14 elements Lithium and sodium react with carbon to form acetylides, Li2C2 and Na2C2, which can also be obtained by reaction of the metal with acetylene. Potassium, rubidium, and caesium react with graphite; their atoms are intercalated between the hexagonal graphite layers, forming graphite intercalation compounds of formulae MC60 (dark grey, almost black), MC48 (dark grey, almost black), MC36 (blue), MC24 (steel blue), and MC8 (bronze) (M = K, Rb, or Cs). These compounds are over 200 times more electrically conductive than pure graphite, suggesting that the valence electron of the alkali metal is transferred to the graphite layers (e.g. ). Upon heating of KC8, the elimination of potassium atoms results in the conversion in sequence to KC24, KC36, KC48 and finally KC60. KC8 is a very strong reducing agent and is pyrophoric and explodes on contact with water. While the larger alkali metals (K, Rb, and Cs) initially form MC8, the smaller ones initially form MC6, and indeed they require reaction of the metals with graphite at high temperatures around 500 °C to form. Apart from this, the alkali metals are |
such strong reducing agents that they can even reduce buckminsterfullerene to produce solid fullerides MnC60; sodium, potassium, rubidium, and caesium can form fullerides where n = 2, 3, 4, or 6, and rubidium and caesium additionally can achieve n = 1. When the alkali metals react with the heavier elements in the carbon group (silicon, germanium, tin, and lead), ionic substances with cage-like structures are formed, such as the silicides M4Si4 (M = K, Rb, or Cs), which contains M+ and tetrahedral ions. The chemistry of alkali metal germanides, involving the germanide ion Ge4− and other cluster (Zintl) ions such as , , , and [(Ge9)2]6−, is largely analogous to that of the corresponding silicides. Alkali metal stannides are mostly ionic, sometimes with the stannide ion (Sn4−), and sometimes with more complex Zintl ions such as , which appears in tetrapotassium nonastannide (K4Sn9). The monatomic plumbide ion (Pb4−) is unknown, and indeed its formation is predicted to be energetically unfavourable; alkali metal plumbides have complex Zintl ions, such as . These alkali metal germanides, stannides, and plumbides may be produced by reducing germanium, tin, and lead with sodium metal in liquid ammonia. Nitrides and pnictides Lithium, the lightest of the alkali metals, is the only alkali metal which reacts with nitrogen at standard conditions, and its nitride is the only stable alkali metal nitride. Nitrogen is an unreactive gas because breaking the strong triple bond in the dinitrogen molecule (N2) requires a lot of energy. The formation of an alkali metal nitride would consume the ionisation energy of the alkali metal (forming M+ ions), the energy required to break the triple bond in N2 and the formation of N3− ions, and all the energy released from the formation of an alkali metal nitride is from the lattice energy of the alkali metal nitride. The lattice energy is maximised with small, highly charged ions; the alkali metals do not form highly charged ions, only forming ions with a charge of +1, so only lithium, the smallest alkali metal, can release enough lattice energy to make the reaction with nitrogen exothermic, forming lithium nitride. The reactions of the other alkali metals with nitrogen would not release enough lattice energy and would thus be endothermic, so they do not form nitrides at standard conditions. Sodium nitride (Na3N) and potassium nitride (K3N), while existing, are extremely unstable, being prone to decomposing back into their |
constituent elements, and cannot be produced by reacting the elements with each other at standard conditions. Steric hindrance forbids the existence of rubidium or caesium nitride. However, sodium and potassium form colourless azide salts involving the linear anion; due to the large size of the alkali metal cations, they are thermally stable enough to be able to melt before decomposing. All the alkali metals react readily with phosphorus and arsenic to form phosphides and arsenides with the formula M3Pn (where M represents an alkali metal and Pn represents a pnictogen – phosphorus, arsenic, antimony, or bismuth). This is due to the greater size of the P3− and As3− ions, so that less lattice energy needs to be released for the salts to form. These are not the only phosphides and arsenides of the alkali metals: for example, potassium has nine different known phosphides, with formulae K3P, K4P3, K5P4, KP, K4P6, K3P7, K3P11, KP10.3, and KP15. While most metals form arsenides, only the alkali and alkaline earth metals form mostly ionic arsenides. The structure of Na3As is complex with unusually short Na–Na distances of 328–330 pm which are shorter than in sodium metal, and this indicates that even with these electropositive metals the bonding cannot be straightforwardly ionic. Other alkali metal arsenides not conforming to the formula M3As are known, such as LiAs, which has a metallic lustre and electrical conductivity indicating the presence of some metallic bonding. The antimonides are unstable and reactive as the Sb3− ion is a strong reducing agent; reaction of them with acids form the toxic and unstable gas stibine (SbH3). Indeed, they have some metallic properties, and the alkali metal antimonides of stoichiometry MSb involve antimony atoms bonded in a spiral Zintl structure. Bismuthides are not even wholly ionic; they are intermetallic compounds containing partially metallic and partially ionic bonds. Oxides and chalcogenides All the alkali metals react vigorously with oxygen at standard conditions. They form various types of oxides, such as simple oxides (containing the O2− ion), peroxides (containing the ion, where there is a single bond between the two oxygen atoms), superoxides (containing the ion), and many others. Lithium burns in air to form lithium oxide, but sodium reacts with oxygen to form a mixture of sodium oxide and sodium peroxide. Potassium forms a mixture of potassium peroxide and potassium superoxide, while rubidium and caesium form the superoxide exclusively. Their reactivity increases going |
down the group: while lithium, sodium and potassium merely burn in air, rubidium and caesium are pyrophoric (spontaneously catch fire in air). The smaller alkali metals tend to polarise the larger anions (the peroxide and superoxide) due to their small size. This attracts the electrons in the more complex anions towards one of its constituent oxygen atoms, forming an oxide ion and an oxygen atom. This causes lithium to form the oxide exclusively on reaction with oxygen at room temperature. This effect becomes drastically weaker for the larger sodium and potassium, allowing them to form the less stable peroxides. Rubidium and caesium, at the bottom of the group, are so large that even the least stable superoxides can form. Because the superoxide releases the most energy when formed, the superoxide is preferentially formed for the larger alkali metals where the more complex anions are not polarised. (The oxides and peroxides for these alkali metals do exist, but do not form upon direct reaction of the metal with oxygen at standard conditions.) In addition, the small size of the Li+ and O2− ions contributes to their forming a stable ionic lattice structure. Under controlled conditions, however, all the alkali metals, with the exception of francium, are known to form their oxides, peroxides, and superoxides. The alkali metal peroxides and superoxides are powerful oxidising agents. Sodium peroxide and potassium superoxide react with carbon dioxide to form the alkali metal carbonate and oxygen gas, which allows them to be used in submarine air purifiers; the presence of water vapour, naturally present in breath, makes the removal of carbon dioxide by potassium superoxide even more efficient. All the stable alkali metals except lithium can form red ozonides (MO3) through low-temperature reaction of the powdered anhydrous hydroxide with ozone: the ozonides may be then extracted using liquid ammonia. They slowly decompose at standard conditions to the superoxides and oxygen, and hydrolyse immediately to the hydroxides when in contact with water. Potassium, rubidium, and caesium also form sesquioxides M2O3, which may be better considered peroxide disuperoxides, . Rubidium and caesium can form a great variety of suboxides with the metals in formal oxidation states below +1. Rubidium can form Rb6O and Rb9O2 (copper-coloured) upon oxidation in air, while caesium forms an immense variety of oxides, such as the ozonide CsO3 and several brightly coloured suboxides, such as Cs7O (bronze), Cs4O (red-violet), Cs11O3 (violet), Cs3O (dark green), |
CsO, Cs3O2, as well as Cs7O2. The last of these may be heated under vacuum to generate Cs2O. The alkali metals can also react analogously with the heavier chalcogens (sulfur, selenium, tellurium, and polonium), and all the alkali metal chalcogenides are known (with the exception of francium's). Reaction with an excess of the chalcogen can similarly result in lower chalcogenides, with chalcogen ions containing chains of the chalcogen atoms in question. For example, sodium can react with sulfur to form the sulfide (Na2S) and various polysulfides with the formula Na2Sx (x from 2 to 6), containing the ions. Due to the basicity of the Se2− and Te2− ions, the alkali metal selenides and tellurides are alkaline in solution; when reacted directly with selenium and tellurium, alkali metal polyselenides and polytellurides are formed along with the selenides and tellurides with the and ions. They may be obtained directly from the elements in liquid ammonia or when air is not present, and are colourless, water-soluble compounds that air oxidises quickly back to selenium or tellurium. The alkali metal polonides are all ionic compounds containing the Po2− ion; they are very chemically stable and can be produced by direct reaction of the elements at around 300–400 °C. Halides, hydrides, and pseudohalides The alkali metals are among the most electropositive elements on the periodic table and thus tend to bond ionically to the most electronegative elements on the periodic table, the halogens (fluorine, chlorine, bromine, iodine, and astatine), forming salts known as the alkali metal halides. The reaction is very vigorous and can sometimes result in explosions. All twenty stable alkali metal halides are known; the unstable ones are not known, with the exception of sodium astatide, because of the great instability and rarity of astatine and francium. The most well-known of the twenty is certainly sodium chloride, otherwise known as common salt. All of the stable alkali metal halides have the formula MX where M is an alkali metal and X is a halogen. They are all white ionic crystalline solids that have high melting points. All the alkali metal halides are soluble in water except for lithium fluoride (LiF), which is insoluble in water due to its very high lattice enthalpy. The high lattice enthalpy of lithium fluoride is due to the small sizes of the Li+ and F− ions, causing the electrostatic interactions between them to be strong: a similar effect |
occurs for magnesium fluoride, consistent with the diagonal relationship between lithium and magnesium. The alkali metals also react similarly with hydrogen to form ionic alkali metal hydrides, where the hydride anion acts as a pseudohalide: these are often used as reducing agents, producing hydrides, complex metal hydrides, or hydrogen gas. Other pseudohalides are also known, notably the cyanides. These are isostructural to the respective halides except for lithium cyanide, indicating that the cyanide ions may rotate freely. Ternary alkali metal halide oxides, such as Na3ClO, K3BrO (yellow), Na4Br2O, Na4I2O, and K4Br2O, are also known. The polyhalides are rather unstable, although those of rubidium and caesium are greatly stabilised by the feeble polarising power of these extremely large cations. Coordination complexes Alkali metal cations do not usually form coordination complexes with simple Lewis bases due to their low charge of just +1 and their relatively large size; thus the Li+ ion forms most complexes and the heavier alkali metal ions form less and less (though exceptions occur for weak complexes). Lithium in particular has a very rich coordination chemistry in which it exhibits coordination numbers from 1 to 12, although octahedral hexacoordination is its preferred mode. In aqueous solution, the alkali metal ions exist as octahedral hexahydrate complexes ([M(H2O)6)]+), with the exception of the lithium ion, which due to its small size forms tetrahedral tetrahydrate complexes ([Li(H2O)4)]+); the alkali metals form these complexes because their ions are attracted by electrostatic forces of attraction to the polar water molecules. Because of this, anhydrous salts containing alkali metal cations are often used as desiccants. Alkali metals also readily form complexes with crown ethers (e.g. 12-crown-4 for Li+, 15-crown-5 for Na+, 18-crown-6 for K+, and 21-crown-7 for Rb+) and cryptands due to electrostatic attraction. Ammonia solutions The alkali metals dissolve slowly in liquid ammonia, forming ammoniacal solutions of solvated metal cation M+ and solvated electron e−, which react to form hydrogen gas and the alkali metal amide (MNH2, where M represents an alkali metal): this was first noted by Humphry Davy in 1809 and rediscovered by W. Weyl in 1864. The process may be speeded up by a catalyst. Similar solutions are formed by the heavy divalent alkaline earth metals calcium, strontium, barium, as well as the divalent lanthanides, europium and ytterbium. The amide salt is quite insoluble and readily precipitates out of solution, leaving intensely coloured ammonia solutions of the alkali metals. In |
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