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e 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 SIVB 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 midcourse correction came eleven hours into t |
he 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 midcourse 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 secondfloor control room there were two identical control rooms in Houston, on the second and third floors, only one of which was used during a miss |
ion. The conference participants concluded that there was little to worry about and that Borman's illness was either a 24hour 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 lau |
nch. The Apollo8 crew used a camera that broadcast in blackandwhite only, using a Vidicon tube. The camera had two lenses, a very wideangle 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 narrowangle 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 highgain 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 32andahalf hours into the flight threeandahalf 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 outgassed 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 hou |
rs 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 midcourse 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 midcourse 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 LOI1. 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 "gono 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 LOI1, 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 illumi |
nating 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, indica |
ting 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 c |
ould be used to return early to the Earth if necessary. He also asked that they receive a "gono 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 11second LOI2 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 behin |
d 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 blackandwhite 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 t |
he 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 youall of you on the good Earth."
The only t |
ask left for the crew at this point was to perform the transEarth 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 reemerged 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 modu |
le 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 liftoff; 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 moni |
tor the spacecraft. As long as the trajectory specialists had calculated everything correctly, the spacecraft would reenter Earth's atmosphere twoandahalf 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 fourminute broadcast. After two uneventful days, the crew prepared f |
or 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 155142 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 apexup Stable 1 orientation by its inflatable bag uprighting system. The first frogman from aircraft carrier arrived 43 minutes after splashdown. Fortyfive 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 m |
agazine 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 fiftyfifty 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 mome |
ntous 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, MercuryAtlas 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 saweither live or delayedthe 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 G |
enesis. O'Hair wanted the courts to ban American astronautswho were all government employeesfrom 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, selfcommunicated 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 pregame show, rec |
iting 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 threedisc 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.
Parts of the mission are dramatized in the 1998 miniseries From the Earth to the Moon episode "1968". The SIVB 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 dr |
ew 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 premired 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 eve |
nts
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 or allegiance; however, astronauts fielded by Russia or the Soviet Union are typically known instead as cosmonauts from the Russian "kosmos" , meaning "space", also borrowed from Greek in order to distinguish them from American or otherwise NATOoriented space travellers. Comparatively recent developments in crewed spaceflight made by China have led to the rise of the term taikonaut from the Mandarin "tikng" , 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 hngtinyun , meaning "heaven navigator" or literally "heavensailing 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 Fdration Aronautique Internationale FAI Sporting Code for astronautics recognizes only flights that exceed the Krmn line, at an altitude of . In the United States, professional, military, and commercial astronauts who travel above an altitude of are awarded astronaut wings.
, 55 |
2 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 24Jim Lovell, John Young and Eugene Cernandid so twice.
, under the U.S. definition, 558 people qualify as having reached space, above altitude. Of eight X15 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 mandays 114.5 manyears in space, including over 100 astronautdays 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 an, the word astronautique astronautic was used. Th |
e 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 nonfiction 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 19001974. The first cosmonaut was Soviet Air Force pilot Yuri Gagarin, also the first person in space. He was part of the first six Russians, with German Titov, Yevgeny Khrunov, Andriyan Nikolayev, Pavel Popovich, and Grigoriy Nelyubov, who were given the title of pilotcosmonaut 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 celestialheaven personnel" is used for Chinese astronauts. Here, , literally "heavennavigating", 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 Englishlanguage 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, ESA envisions 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 .
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 Sovietled 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 me |
aning '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 Internationa |
l Space Station in a mission coordinated by NASA and Roscosmos is a spaceflight participant
one who flies above in a nonNASA 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 generallyaccepted but unofficial term for a paying noncrew passenger who flies a private nonNASA 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 crite |
ria 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 "demonstrated 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 15minute suborbital 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 STS7, on 18 June 1983. In 19 |
92, Mae Jemison became the first African American woman to travel in space aboard STS47.
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 Asianborn astronaut in 1968.
The Soviet Union, through its Intercosmos program, allowed people from other "socialist" i.e. Warsaw Pact and other Sovietallied countries to fly on its missions, with the notable exceptions of France and Austria participating in Soyuz TM7 and Soyuz TM13, respectively. An example is Czechoslovak Vladimr Remek, the first cosmonaut from a country other than the Soviet Union or the United States, who flew to space in 1978 on a SoyuzU rocket. Rakesh Sharma becam |
e the first Indian citizen to travel to space. He was launched aboard Soyuz T11, 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 Mndez 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 AlSaud 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 nonUS citizen to fly in a US spacecraft. In 1984, Marc Garneau became the firs |
t of eight Canadian astronauts to fly in space through 2010.
In 1985, Rodolfo Neri Vela became the first Mexicanborn 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 reentry 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 lasting 7 minutes on July 20, 2021. 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.
On the same flight as Daemen was 82 year, 6monthold Wally Funk, one of the women dubbed the Mercury 13, and now the oldest person in space. She is the first of the Mercury 13 to reach space, although the group was trained concurrently with the allmale Mercury 7, who would all engage in space travel. The oldest person to reach orbit is John Glenn, one of the Mercury 7, who was 77 when he flew on STS95. For suborbital 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 ChangDiaz. 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 nongovernment mil |
estones
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 X15 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 nongovernmental space traveler was Byron K. Lichtenberg, a researcher from the Massachusetts Institute of Technology who flew on STS9 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 selffunded space tourist was Dennis Tito on board the Russian spacecraft Soyuz TM3 on 28 April 2001.
Selffunded 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 111 October 2005 ISS
Anousheh Ansari Iranian American 1829 September 2006 ISS
Charles Simonyi Hungarian American 721 April 2007 ISS, 26 March 8 April 2009 ISS
Richard Garriott British American 1224 October 2008 ISS
Guy Lalibert Canadian 30 Septembe |
r 2009 11 October 2009 ISS
Jared Isaacman American 1518 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. Astronautsintraining astronaut candidates may also experience short periods of weightlessness microgravity in an aircraft called the "V |
omit Comet," the nickname given to a pair of modified KC135s retired in 2000 and 2004, respectively, and replaced in 2005 with a C9 which perform parabolic flights. Astronauts are also required to accumulate a number of flight hours in highperformance jet aircraft. This is mostly done in T38 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 a |
t least two years of related professional experience obtained after degree completion or at least 1,000 hours pilotincommand time on jet aircraft.
The candidate must be able to pass the NASA longduration 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 MetcalfLindenburger.
Barbara Morgan, selected as backup 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 hund |
reds 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 nonexpert 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 nearweightlessness of space. Microorganisms have been observed to survive the vacuum of outer space.
On 31 December 2012, a NASAsupported 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 longduration space missions. The syndrome, known as visual impairment intracranial pressure VIIP, has been reported in nearly twothirds 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, NASAfunded researchers found that lengthy journeys into outer space, including travel to the planet Mars, may substantially damage th |
e 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 longduration 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 PilotCosmonaut 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 activeduty 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 fourte |
en men and four women have lost their lives during four space flights. By nationality, thirteen were American, four were Russian Soviet Union, and one was Israeli.
, eleven people all men have lost their lives 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 c |
areer astronauts, the memorial includes the names of an X15 test pilot, a U.S. Air Force officer who died while training for a thenclassified 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 toward the Irish in general.
In English writing, the phrase "a modest proposal" is now conventionally an allusion to this style of straightfaced 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 theninfluential 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 tha |
t Swift's main target in A Modest Proposal was not the conditions in Ireland, but rather the cando 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 cureall solution. A memorable example of these sorts of schemes "involved the idea of running the poor through a jointstock 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 fauxmathematical philosop |
hy. 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, textbookapproved 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, thoughtfu |
l, 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 childrenTertullian 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 andwhile not being a completely satirical texthas 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 deliberati |
ons 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 a |
nd 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 moralpolitical 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 maximpe |
ople are the riches of a nationapplies 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.
The public's reaction
Swift's essay created a backl |
ash within the 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 intimated that he certainly understood the message, and interpreted it as a work of comedy
12 February 172930
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 postsecondary 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.
The essay's approach has been copied many times. In his book A Modest Proposal 1984, the evangelical author Francis Schaeffer emulated Swift's work in a social conservative polemic against abortion and euthanasia, |
imagining a future dystopia that advocates recycling of aborted embryos, fetuses, and some disabled infants with compound intellectual, physical and physiological difficulties. Such Baby Doe Rules cases were then a major concern of the US antiabortion movement of the early 1980s, which viewed selective treatment of those infants as disability discrimination.
In his book A Modest Proposal for America 2013, statistician Howard Friedman opens with a satirical reflection of the extreme drive to fiscal stability by ultraconservatives.
In the 1998 edition of The Handmaid's Tale by Margaret Atwood there is a quote from A Modest Proposal before the introduction.
A Modest Video Game Proposal is the title of an open letter sent by activistformer attorney Jack Thompson on 10 October 2005. He proposed that someone should "create, manufacture, distribute, and sell a video game" that would allow players to act out a scenario in which the game character kills video game developers.
Hunter S. Thompson's Fear and Loathin |
g in America The Brutal Odyssey of an Outlaw Journalist includes a letter in which he uses Swift's approach in connection with the Vietnam War. Thompson writes a letter to a local Aspen newspaper informing them that, on Christmas Eve, he is going to use napalm to burn a number of dogs and hopefully any humans they find. The letter protests against the burning of Vietnamese people occurring overseas.
The 2013 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.
On 30 November 2017, Jonathan Swift's 350th birthday, The Washington Post published a column entitled "Why Alabamians should consider eating Democrats' babies", by Alexandra Petri.
In July 2019, E. Jean Carroll published a book titled What Do We Need Men For? A Modest Proposal, discussing problematic behaviour of m |
ale humans.
On 3 October 2019, a satirist spoke up at an event for Alexandria OcasioCortez, claiming that a solution to the climate crisis was "we need to eat the babies". The individual also wore a Tshirt saying "Save The Planet, Eat The Children". This stunt was understood by many as a modern application of A Modest Proposal.
On 16 January 2022, San Francisco Chronicle published an editorial by Joe Matthews titled "Opinion Want true equity? I propose, modestly, forcing California parents to swap children" in which the author makes "a modest proposal" recommending that rich people give their children to poor people and poor people give their children to rich people as a way of achieving class equity.
Notes
References
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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 DevereuxCourt near the MiddleTemple, 1730.
Proposal to eat the children a short movie based upon Swift's novel.
Essays by Jonathan Swift
Satirical essays
Pamphlets
18thcentury 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 sblock of the periodic table. All alkali metals have their outermost electron in an sorbital 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 wellcharacterised 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 was successful. However, ununennium may not be an alkali metal due to relativistic effects, which are predicted to have a large influence on the ch |
emical 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 bestknown 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 sodiumvapour 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 and potassium are also 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 HenriLouis 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 aqueou |
s 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 Jos Bonifcio de Andrada in a mine on the island of Ut, Sweden. However, it was not until 1817 that Johan August Arfwedson, then working in the laboratory of the chemist Jns 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 "lithionlithina", from the Greek word o transliterated as lithos, meaning "stone", to reflect its discovery in a solid m |
ineral, 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 Dbereiner 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 Drkheim, 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 skyblue line for caesium derived from the Latin word caesius, m |
eaning skyblue.
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 t |
o 11. After the introduction of the 18column table, the group IB elements were moved to their current position in the dblock, 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 actinium227, 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 actinium227. Various tests eliminated the possibility of the unknown element being thorium, radium, lead, bismuth, or thallium. The new product exhibi |
ted 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 actinium227. Perey then attempted to determine the proportion of beta decay to alpha decay in actinium227. Her first test put the alpha branching at 0.6, a figure that she later revised to 1.
The next element below francium ekafrancium in the periodic table would be ununennium Uue, element 119. The synthesis of ununennium was first attempted in 1985 by bombarding a target of einsteinium254 with calcium48 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 einsteinium254, which is favoured for production of ultraheavy elements because of its large mass, relatively long halflife o |
f 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 OddoH |
arkins 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, ber |
yllium 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 triplealpha 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 lowdensity 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 nearequal 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.
Francium223, the only naturally occurring isotope of francium, is the product of the alpha decay of actinium227 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 halflife 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 confi |
guration, 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 bodycentered 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 sorbital 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 silvercoloured 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 bodycentered cubic crystal structure, and have distinctive flame colours because their outer s elect |
ron 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 attai |
n 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 ssubshells, 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", HNa both ions being complexed, as opposed to the usual sodium hydride, NaH 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 MH2On, 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 m |
etal 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 welldefined 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 LiH2O4 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 LiH2O4 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 NaH2O6 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 KH2O8 and RbH2O8 ions, which have the square antiprismatic structure, and that caesium forms the 12coordinate CsH2O12 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 airconditioners.
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 ener |
gies 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 kJmol and the enthalpy of dissociation of the Fr2 molecule 42.1 kJmol. The CsFr molecule is polarised as CsFr, 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 oddodd both proton and neutron number are odd or oddeven proton number is odd, but neutron number is even. Oddodd nuclei have even mass numbers, whereas oddeven nuclei have odd mass numbers. Oddodd primordial nuclides are rare because most oddodd nuclei are highly unstable with respect to beta decay, because the decay products are eveneven, and are therefore more strongly bound, due to nuclear pairing effects.
Due to the great rarity of oddodd nuclei, almost all the primordial isotopes of the alkali metals are oddeven the exceptions being the light stable isotope lithium6 and the longlived radioisotope potassium40. For a given odd mass number, there ca |
n be only a single betastable nuclide, since there is not a difference in binding energy between evenodd and oddeven comparable to that between eveneven and oddodd, leaving other nuclides of the same mass number isobars free to beta decay toward the lowestmass nuclide. An effect of the instability of an odd number of either type of nucleons is that oddnumbered elements, such as the alkali metals, tend to have fewer stable isotopes than evennumbered 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 sodium22 and sodium24 are trace radioisotopes produced cosmogenically, potassium40 and rubidium87 have very long halflives and thus occur naturally, and all isotopes of francium are radioactive. Caesium was also th |
ought 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 longlived radioisotope of potassium, potassium40, 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 longlived radioisotope rubidium87.
Caesium137, with a halflife of 30.17 years, is one of the two principal mediumlived fission products, along with strontium90, 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. Caesium137 undergoes highenergy beta decay and eventually becomes stable barium137. It is a strong emitter of ga |
mma radiation. Caesium137 has a very low rate of neutron capture and cannot be feasibly disposed of in this way, but must be allowed to decay. Caesium137 has been used as a tracer in hydrologic studies, analogous to the use of tritium. Small amounts of caesium134 and caesium137 were released into the environment during nearly all nuclear weapon tests and some nuclear accidents, most notably the Goinia accident and the Chernobyl disaster. As of 2005, caesium137 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 shorttomediumlifetime 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 instanc |
e, 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. |
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