Astronaut

• 1. Introduction

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  An astronaut, in its oldest sense, is a star sailor. The word comes directly from the Ancient Greek: astron, meaning star, and nautes, meaning sailor. But the people this word describes have sailed far beyond stars. As of April 2026, 781 humans from 55 countries have left Earth's atmosphere. Some orbited the planet for three days. Some walked on the Moon. One man, Russian cosmonaut Oleg Kononenko, has spent more than 1,100 days in space across his career. What turns a person into a star sailor? What does the title actually mean, who decides, and what happens to the human body when it leaves the world it was built for? Those are the questions this documentary will answer.

• 2. A Word With Many Owners

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  In 1959, before either superpower had sent a single person into space, NASA Administrator T. Keith Glennan and his Deputy Administrator Hugh Dryden sat down to argue about a word. Dryden preferred "cosmonaut," reasoning that the prefix astro implied flight to the stars while future missions would travel through the broader cosmos. Most members of the NASA Space Task Group disagreed. They preferred "astronaut," and common usage carried the day. When the Soviet Union launched Yuri Gagarin in 1961, it chose the other path, adopting the term that anglicizes as cosmonaut. The credit for coining that Russian word goes to Soviet aeronautics pioneer Mikhail Tikhonravov, who lived from 1900 to 1974. A third term emerged decades later, when China sent Yang Liwei into orbit aboard the Shenzhou 5 in 2003. English-language media began using taikonaut, drawn from the Mandarin taikong meaning space. Chinese official sources, however, use hangtian yuan, which translates roughly as celestial navigator. The origin of the word taikonaut is disputed; one documented early use traces to a Malaysian writer named Chiew Lee Yih, who used it in online newsgroups as early as May 1998.

• 3. Who Counts as One

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  Not everyone who rides a rocket is called an astronaut, and the criteria have shifted sharply over the decades. In the United States, three separate agencies each apply their own definition: NASA, the Federal Aviation Administration, and the military. NASA and the military reserve the term for their own personnel who meet specific criteria. The FAA, by contrast, created the category of commercial astronaut when SpaceShipOne made its suborbital flight in 2004. Its standard requires that the person demonstrate activities essential to public safety or that contribute to human spaceflight safety. On the 20th of July 2021, the FAA rewrote that definition directly in response to the private suborbital flights of Jeff Bezos and Richard Branson. The revised language excluded both men. The Fédération Aéronautique Internationale draws the boundary at 100 km altitude; the United States military and NASA use 80 km. NASA also introduced a separate category in 2020 for private astronauts aboard commercially dedicated ISS missions, though as of that year no one had yet qualified for it. The term "spaceflight participant" was agreed upon by NASA and the Russian Federal Space Agency specifically to separate paying tourists from professional crew members. For its 2022 Astronaut Group, the European Space Agency tried something new: recruiting a candidate with a physical disability, using the term parastronauts. John McFall was selected for that role on the 23rd of November 2022. He has rejected the term.

• 4. Firsts That Shaped the Record

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  Yuri Gagarin launched on the 12th of April 1961, aboard Vostok 1, and completed an orbit of Earth in 108 minutes. Less than a month later, on the 5th of May 1961, Alan Shepard rode Freedom 7 on a 15-minute suborbital arc to become the first American in space. The first woman in space was Soviet Valentina Tereshkova, who launched on the 16th of June 1963, aboard Vostok 6 and remained in orbit for nearly three days. Tereshkova was only honorarily inducted into the Soviet Air Force, which did not accept female pilots at the time. In the United States, the first woman to reach orbit was Sally Ride, who flew on Space Shuttle Challenger's mission STS-7 on the 18th of June 1983. Cosmonaut Alexei Leonov performed the first spacewalk on the 18th of March 1965, stepping outside Voskhod 2 for a few minutes. American astronaut Ed White made the first American spacewalk two and a half months later on Gemini 4. The Intercosmos program opened Soviet spacecraft to citizens of allied and friendly nations, making Czechoslovak Vladimír Remek the first person from a country other than the United States or Soviet Union to fly in space, in 1978. In 2001, American Dennis Tito became the first self-funded space tourist, paying for a ride aboard the Russian spacecraft Soyuz to the International Space Station. The first paying space traveler before Tito was journalist Toyohiro Akiyama, who flew to Mir in December 1990 as part of an estimated twelve-million-dollar deal with a Japanese television station.

• 5. Records at the Edges

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  At the upper end of age, William Shatner was 90 years old when he made a suborbital flight on Blue Origin NS-18, making him the oldest person to reach space. The oldest person to reach orbit is John Glenn, who was 77 when he flew on STS-95. Glenn was one of the original Mercury Seven. At the other end, Oliver Daemen was 18 years and 11 months old when he flew on Blue Origin NS-16, breaking a record previously held by Soviet cosmonaut Gherman Titov, who was 25 when he flew Vostok 2. Titov remains the youngest person to reach orbit; he circled the planet 17 times and was also the first person to suffer space sickness and the first to sleep in space. For duration, Russian Valeri Polyakov spent 438 days continuously in space, the longest single stay on record. The farthest any human has traveled from Earth is 406,771 km, a record set by Reid Wiseman, Victor Glover, Christina Koch, and Canadian Jeremy Hansen during the Artemis II lunar flyby mission in 2026. The previous record dated to the Apollo 13 emergency in 1970, when Jim Lovell, Jack Swigert, and Fred Haise reached 401,056 km. Peggy Whitson holds the record for the most cumulative time in space by a woman, at 695 days.

• 6. Training and Selection

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  NASA selected its first astronauts in 1959, drawing almost exclusively from military jet pilots. Early eligibility was so narrowly defined that neither John Glenn nor Scott Carpenter, both members of the Mercury Seven, held a university degree at the time of their selection. Modern requirements look quite different. Candidates must be United States citizens with at least a master's degree in a STEM field, plus either two years of relevant professional experience or a minimum of 1,000 hours as a pilot-in-command on jet aircraft. The physical standards for long-duration flight must also be met, along with demonstrated skills in leadership, teamwork, and communications. Once accepted, NASA astronaut candidates go through twenty months of training. Part of that training takes place in NASA's Neutral Buoyancy Laboratory, a massive pool used to simulate spacewalk conditions. Candidates also fly in an aircraft informally nicknamed the Vomit Comet, a modified aircraft that flies parabolic arcs to produce short periods of weightlessness. The pair of KC-135 aircraft originally used for this were retired in 2000 and 2004, replaced in 2005 by a C-9. High-performance jet flight hours are accumulated mainly in T-38 aircraft out of Ellington Field, chosen for its proximity to the Johnson Space Center. A later addition to the astronaut pipeline was the Educator Astronaut program, first selecting candidates in 2004. By 2007, three educators had been selected: Joseph Acaba, Richard Arnold, and Dorothy Metcalf-Lindenburger. The program grew out of the Teacher in Space program of the 1980s, under which Barbara Morgan was selected as backup to Christa McAuliffe in 1985.

• 7. What Space Does to the Body

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  The International Space Station's roster of health problems for long-duration crew members is substantial: decompression sickness, bone and muscle loss, sleep disturbances, immune changes, orthostatic intolerance, and radiation injury all appear on the list. A 2006 Space Shuttle experiment found that Salmonella typhimurium became more virulent in space. By 2017, bacteria were found to be more resistant to antibiotics in near-weightlessness. On the 2nd of November 2017, researchers published MRI findings showing structural and positional changes in the brains of astronauts who had taken long-duration missions, with greater changes linked to longer trips. A condition called visual impairment intracranial pressure, or VIIP, has been reported in nearly two-thirds of space explorers after long ISS stays. A 2020 study of eight male Russian cosmonauts found that extended spaceflight led to new motor skills including improved dexterity, but also slightly weakened vision, and it provided the first clear evidence of sensorimotor neuroplasticity from spaceflight. NASA-funded researchers reported in October 2018 that long journeys, including a hypothetical trip to Mars, could substantially damage gastrointestinal tissue. A study from Russia's Moscow Institute of Physics and Technology, published in April 2019, found that neutron and gamma radiation temporarily hinders the formation of new cells in the brain's memory centers, without affecting intellectual capability overall. On the 31st of December 2012, a NASA-supported study reported that spaceflight may accelerate the onset of Alzheimer's disease. The medical techniques developed through the Advanced Diagnostic Ultrasound in Microgravity Study, which used former ISS commanders Leroy Chiao and Gennady Padalka as subjects, are now being applied to professional and Olympic sports injuries and to emergency care in rural settings on Earth.

• 8. Loss and Memory

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  Eighteen astronauts, fourteen men and four women, have died during four space flights. Thirteen were American, four were Soviet, and one was Israeli. Eleven more, all men, died in training: eight Americans and three Russians. Six of those training deaths were caused by crashes of jet aircraft; one person drowned during water recovery training; four died in fires in pure-oxygen environments. In 1971, astronaut David Scott left a small statuette called Fallen Astronaut on the surface of the Moon during the Apollo 15 mission. Alongside it he placed a list of eight astronauts and six cosmonauts known at the time to have died in service. Back on Earth, the Space Mirror Memorial on the grounds of the Kennedy Space Center Visitor Complex, maintained by the Astronauts Memorial Foundation, records the names of those who died during spaceflight and training in United States space programs. Beyond the twenty NASA career astronauts it commemorates, the memorial includes the name of an X-15 test pilot, a United States Air Force officer who died while training for a then-classified military program, and one civilian spaceflight participant. Space travel had claimed more than a hundred astronaut-days of spacewalks by the time the total time humans have spent beyond Earth exceeded 41,790 man-days, the equivalent of roughly 114 and a half man-years in orbit.