Astronaut | Definition, Facts, & Training

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border-left-sm open"> <div class="drawer d-flex flex-column open"> <div class="left-rail-section-content"> <div class="topic-left-rail-header text-truncate bg-gray-50 position-relative text-right d-flex align-items-center"> <div class="tlr-title px-20 py-15 text-left"> <em class="material-icons text-gray-400 d-lg-none" data-icon="toc"></em> <a class="font-serif font-weight-bold text-black link-blue" href="https://www.britannica.com/topic/astronaut">astronaut</a> </div> <button aria-label="Close" class="js-sections-close-button btn-link btn-sm btn d-lg-none position-absolute top-0 p-10 right-0" > <em class="material-icons font-26" data-icon="close"></em> </button> </div> <div class="section-content pl-10 pr-20 pl-sm-50 pr-sm-60 pl-lg-5 pr-lg-10 pt-10 pt-lg-0 bg-gray-50 clear-catfish-ad"> <div class="toc mb-20"> <div class="font-serif font-14 font-weight-bold mx-15 mb-15 mt-20"> Table of Contents </div> <ul class="list-unstyled my-0" data-level="h1"><li data-target="#ref1"><div class="pl-25"><a class="link-gray-900 w-100" href="/topic/astronaut">Introduction</a></div><div class="ml-40 toc-drawer sub-toc-drawer"></div></li><li data-target="#ref262029"><div class="d-flex align-items-center"><div class="ml-25"></div><a class="w-100 link-gray-900" href="/topic/astronaut#ref262029">History and highlights</a></div><div class="ml-40 toc-drawer sub-toc-drawer"></div></li><li data-target="#ref262030"><div class="d-flex align-items-center"><div class="ml-25"></div><a class="w-100 link-gray-900" href="/topic/astronaut/Astronaut-training">Astronaut training</a></div><div class="ml-40 toc-drawer sub-toc-drawer"></div></li><li data-target="#ref301283"><div class="d-flex align-items-center"><div class="ml-25"></div><a class="w-100 link-gray-900" href="/topic/astronaut/Notable-astronauts">Notable astronauts</a></div><div class="ml-40 toc-drawer sub-toc-drawer"></div></li></ul> <a class="toc-extra-link link-gray-900" href="https://www.britannica.com/topic/astronaut/additional-info">References & Edit History</a> <a class="toc-extra-link link-gray-900" href="/facts/astronaut">Quick Facts & Related Topics</a> </div> <div class="tlr-media-slider pb-10 mb-30"> <a class="section-header link-gray-900 font-serif font-14 font-weight-bold mb-10 mx-10" href="https://www.britannica.com/topic/astronaut/images-videos">Images & Videos</a> <div class="slider js-slider position-relative d-inline-flex align-items-center mw-100 "> <div class="slider-container js-slider-container overflow-hidden d-flex overflow-hidden text-nowrap ml-15"> <a href="https://cdn.britannica.com/18/102418-050-80A86A9E/hands-Robert-Gibson-Atlantis-Vladimir-Dezhurov-Russian-June-29-1995.jpg" data-href="/media/1/40000/101996" class="media-overlay-link d-inline-block mr-5"> <img loading="lazy" src="https://cdn.britannica.com/18/102418-004-CAD59B2B/hands-Robert-Gibson-Atlantis-Vladimir-Dezhurov-Russian-June-29-1995.jpg" alt="Robert Gibson and Vladimir Dezhurov" height="50" /> </a> <a href="https://cdn.britannica.com/01/102501-050-E87BC69D/Pavel-Popovich-flight-Vostok-4-15-1962.jpg" data-href="/media/1/40000/101997" class="media-overlay-link d-inline-block mr-5"> <img loading="lazy" src="https://cdn.britannica.com/01/102501-004-A6D5A92C/Pavel-Popovich-flight-Vostok-4-15-1962.jpg" alt="Pavel Popovich on Vostok 4" height="50" /> </a> <a href="https://cdn.britannica.com/08/76508-050-C956D392/John-H-Glenn-Jr-Friendship-7-launch-Feb-20-1962.jpg" data-href="/media/1/40000/100199" class="media-overlay-link d-inline-block mr-5"> <img loading="lazy" src="https://cdn.britannica.com/08/76508-004-8350D452/John-H-Glenn-Jr-Friendship-7-launch-Feb-20-1962.jpg" alt="John Glenn entering Friendship 7" height="50" /> </a> <a href="https://cdn.britannica.com/22/115022-050-FA9D6901/Yury-Alekseyevich-Gagarin-1961.jpg" data-href="/media/1/40000/112294" class="media-overlay-link d-inline-block mr-5"> <img loading="lazy" src="https://cdn.britannica.com/22/115022-004-8255E1E1/Yury-Alekseyevich-Gagarin-1961.jpg" alt="Yuri Gagarin" height="50" /> </a> <a href="https://cdn.britannica.com/54/8354-050-B6B3B6EA/Valentina-Tereshkova-space-orbit-spacecraft-Vostok-6-June-1963.jpg" data-href="/media/1/40000/100281" class="media-overlay-link d-inline-block mr-5"> <img loading="lazy" src="https://cdn.britannica.com/54/8354-004-81820663/Valentina-Tereshkova-space-orbit-spacecraft-Vostok-6-June-1963.jpg" alt="Valentina Tereshkova" height="50" /> </a> <a href="https://cdn.britannica.com/21/21521-050-02D43180/Sally-Ride-Challenger-space-flight-June-1983.jpg" data-href="/media/1/40000/100201" class="media-overlay-link d-inline-block mr-5"> <img loading="lazy" src="https://cdn.britannica.com/21/21521-004-B4EB6CE5/Sally-Ride-Challenger-space-flight-June-1983.jpg" alt="Sally Ride" height="50" /> </a> <a href="https://cdn.britannica.com/89/102389-050-DAD674EF/Robert-L-Satcher-Jr-aircraft-training-KC-135-Oct-13-2004.jpg" 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Logsdon</div> <div class="editor-description font-12 font-serif mt-5 clamp-description text-black">John M. Logsdon is Professor Emeritus of Political Science and International Affairs at George Washington University’s Elliott School of International Affairs. He was a member of the NASA Advisory Council...</div> </a> <div data-popper-arrow></div> </div> <span class="btn btn-link editor-link p-0 qa-byline-link gtm-byline font-12 byline-contributor text-decoration-underline"> John M. Logsdon</span></div> <div class="font-serif font-12 text-gray-700"> <span class="qa-fact-checked-by">Fact-checked by</span> <div class="editor-popover popover p-0"> <a class="d-block p-20 qa-editor-popup font-12" href="/editor/The-Editors-of-Encyclopaedia-Britannica/4419" > <div class="editor-title font-16 font-weight-bold">The Editors of Encyclopaedia Britannica</div> <div class="editor-description font-12 font-serif mt-5 text-black">Encyclopaedia Britannica's editors oversee subject areas in which they have extensive knowledge, whether from years of experience gained by working on that content or via study for an advanced degree. They write new content and verify and edit content received from contributors.</div> </a> <div data-popper-arrow></div> </div> <span class="btn btn-link editor-link p-0 qa-byline-link font-12 "> The Editors of Encyclopaedia Britannica</span></div> <div class="last-updated font-12 font-serif"> <span class="text-gray-700"> Last Updated: <time datetime="2025-02-25T00:00:00CST" >Feb 25, 2025</time> •</span> <a class="byline-edit-history" href="https://www.britannica.com/topic/astronaut/additional-info#history" rel="nofollow">Article History</a> </div></div> </div> <button class="d-flex d-lg-none btn btn-outline-blue border rounded-sm shadow-sm mobile-toc-button gtm-mobile-toc-inline-button d-none d-sm-block js-sections-inline-button module-spacing btn d-lg-none"> <em class="material-icons mr-5 ml-n10 my-n5 md-icon" data-icon="toc"></em> Table of Contents </button> <div class="d-flex d-sm-none flex-row"> <button class="d-flex d-lg-none btn btn-outline-blue border rounded-sm shadow-sm mobile-toc-button gtm-mobile-toc-inline-button js-sections-inline-button module-spacing"> <em class="material-icons mr-5 ml-n10 my-n5 md-icon" data-icon="toc"></em> Table of Contents </button> <button class="ai-ask-button btn btn-sm border-2 btn-outline-red-400 border-red-400 module-spacing js-inline-ai-ask-button p-10 ml-5"> Ask the Chatbot </button> </div> <div class="js-qf-module qf-module px-40 px-sm-20 py-15 mx-auto module-spacing font-14 bg-gray-50 rounded"> <div class="facts-list mt-10"> <div class=""> <div class="js-fact mb-10 line-clamp clamp-3"> <dl> <dt>Key People: </dt> <dd><a href="/biography/Frank-Rubio" topicid="2251108">Frank Rubio</a></dd> <dd><a href="/biography/Jessica-Watkins" topicid="2242997">Jessica Watkins</a></dd> <dd><a href="/biography/Norishige-Kanai" topicid="2120301">Norishige Kanai</a></dd> <dd><a href="/biography/Kate-Rubins" topicid="2087007">Kate Rubins</a></dd> <dd><a href="/biography/Robert-Henry-Lawrence-Jr" topicid="1451398">Robert Henry Lawrence, Jr.</a></dd> </dl> <button class="js-more-btn d-none btn btn-unstyled font-12 bg-gray-50" aria-label="Toggle more/less fact data"> <em class="js-content link-blue">(Show more)</em> </button> </div> </div> <div class=""> <div class="js-fact mb-10 line-clamp clamp-3"> <dl> <dt>Related Topics: </dt> <dd><a href="/science/space-exploration" topicid="557348">space exploration</a></dd> <dd><a href="/technology/extravehicular-activity-backpack" topicid="199148">extravehicular activity backpack</a></dd> <dd><a href="/science/spacewalk" topicid="1110343">spacewalk</a></dd> <dd><a href="/science/untethered-spacewalk" topicid="2114203">untethered spacewalk</a></dd> <dd><a href="/science/manned-spacecraft" topicid="362515">crewed spacecraft</a></dd> </dl> <button class="js-more-btn d-none btn btn-unstyled font-12 bg-gray-50" aria-label="Toggle more/less fact data"> <em class="js-content link-blue">(Show more)</em> </button> </div> </div> <div class=""> <div class="js-fact mb-10 line-clamp clamp-3"> <dl> <dt>On the Web: </dt> <dd><a href="https://www.hup.harvard.edu/file/feeds/PDF/9780674257726_sample.pdf" target="_blank">Harvard University Press - The End of Astronauts (PDF)</a> (Feb. 25, 2025)</dd> </dl> <button class="js-more-btn d-none btn btn-unstyled font-12 bg-gray-50" aria-label="Toggle more/less fact data"> <em class="js-content link-blue">(Show more)</em> </button> </div> <div class="text-center"> <a class="btn btn-sm btn-link p-0" href="/facts/astronaut"> See all related content </a> </div> </div> </div> </div><span class="marker before-article"></span><section data-level="1" id="ref1"><span class="marker PREMOD1 mod-inline"></span><p class="topic-paragraph"><strong><span id="ref231424"></span>astronaut</strong>, <a class="md-dictionary-link md-dictionary-tt-off mw" data-term="designation" href="https://www.merriam-webster.com/dictionary/designation" data-type="MW">designation</a>, derived from the Greek words for “star” and “sailor,” commonly applied to an individual who has flown in outer space. More specifically, in the West, <em>astronaut</em> refers to those from the <span id="ref943331"></span><a href="https://www.britannica.com/place/United-States" class="md-crosslink " data-show-preview="true">United States</a>, <a href="https://www.britannica.com/place/Canada" class="md-crosslink autoxref " data-show-preview="true">Canada</a>, Europe, and <a href="https://www.britannica.com/place/Japan" class="md-crosslink autoxref " data-show-preview="true">Japan</a> who travel into space. Those <span id="ref943332"></span><a href="https://www.britannica.com/place/Soviet-Union" class="md-crosslink " data-show-preview="true">Soviet</a> and later Russian individuals who travel into space are known as <em>cosmonauts</em> (from the Greek words for “universe” and “sailor”). In <a href="https://www.britannica.com/place/Russia" class="md-crosslink autoxref " data-show-preview="true">Russia</a> the word <em>cosmonaut</em> is used for space travelers of all nations. In the West, Chinese space travelers have come to be referred to as <em>taikonauts</em> (from the Chinese word for “space” and the Greek word for “sailor”), but in China the word <em>yuhangyuan</em> (from the Chinese words for “space” and “traveler”) is used.</p><span class="marker MOD1 mod-inline"></span></section> <span class="marker h2"></span><section data-level="1" id="ref262029"> <h2 class="h1">History and highlights</h2> <span class="marker PREMOD2 mod-inline"></span><div class="assemblies"><div class="w-100"><figure class="md-assembly m-0 mb-md-0 card card-borderless print-false" data-assembly-id="101997" data-asm-type="image"><div class="md-assembly-wrapper card-media" data-type="image"><a href="https://cdn.britannica.com/01/102501-050-E87BC69D/Pavel-Popovich-flight-Vostok-4-15-1962.jpg" class="gtm-assembly-link position-relative d-flex align-items-center justify-content-center media-overlay-link card-media" data-href="/media/1/40000/101997"><picture><source media="(min-width: 680px)" srcset="https://cdn.britannica.com/01/102501-050-E87BC69D/Pavel-Popovich-flight-Vostok-4-15-1962.jpg?w=300"><img src="https://cdn.britannica.com/01/102501-050-E87BC69D/Pavel-Popovich-flight-Vostok-4-15-1962.jpg?w=300" alt="Pavel Popovich on Vostok 4" data-width="1500" data-height="1124" loading="eager"></picture><button class="magnifying-glass btn btn-circle position-absolute shadow btn-white top-10 right-10" aria-label="Zoom in"><em class="material-icons link-blue" data-icon="zoom_in"></em></button></a></div><figcaption class="card-body"><div class="md-assembly-caption text-muted font-14 font-serif line-clamp"><span><a class="gtm-assembly-link md-assembly-title font-weight-bold d-inline font-sans-serif mr-5 media-overlay-link" href="https://cdn.britannica.com/01/102501-050-E87BC69D/Pavel-Popovich-flight-Vostok-4-15-1962.jpg" data-href="/media/1/40000/101997">Pavel Popovich on Vostok 4</a><span>Cosmonaut Pavel Popovich during the Vostok 4 flight, August 12–15, 1962. </span><button class="js-more-btn d-none btn btn-unstyled font-12 bg-white js-content" aria-label="Toggle more/less fact data"><span class="link-blue">(more)</span></button></span></div></figcaption></figure></div></div><p class="topic-paragraph">As of 2022, 587 individuals from 41 countries had gone into orbit; 518 of these space fliers were men, and 69 were women. The longest time spent in space on one mission is the 438 days spent aboard the Russian <a href="https://www.britannica.com/technology/space-station" class="md-crosslink autoxref " data-show-preview="true">space station</a> <a href="https://www.britannica.com/topic/Mir-Soviet-Russian-space-station" class="md-crosslink " data-show-preview="true">Mir</a> by cosmonaut <a href="https://www.britannica.com/biography/Valery-Vladimirovich-Polyakov" class="md-crosslink " data-show-preview="true">Valery Polyakov</a> in 1994–95. The longest individual <a class="md-dictionary-link md-dictionary-tt-off mw" data-term="cumulative" href="https://www.merriam-webster.com/dictionary/cumulative" data-type="MW">cumulative</a> time is the 878 days spent by cosmonaut Gennady Padalka on one mission to Mir and four missions to the <a href="https://www.britannica.com/topic/International-Space-Station" class="md-crosslink autoxref " data-show-preview="true">International Space Station</a>. Two U.S. astronauts, <span id="ref1270943"></span><a href="https://www.britannica.com/biography/Franklin-Chang-Diaz" class="md-crosslink " data-show-preview="true">Franklin Chang-Díaz</a> and <span id="ref1270944"></span><a href="https://www.britannica.com/biography/Jerry-Ross" class="md-crosslink " data-show-preview="true">Jerry Ross</a>, made seven spaceflights, the most by any single individual. The youngest person to go into space was Oliver Daemen, who was 18 when he flew on the first flight of Blue Origin’s suborbital <a href="https://www.britannica.com/technology/spacecraft" class="md-crosslink autoxref " data-show-preview="true">spacecraft</a> New Shepard in 2021. The oldest astronaut was <a href="https://www.britannica.com/biography/William-Shatner" class="md-crosslink " data-show-preview="true">William Shatner</a>, who was 90 when he flew on the second New Shepard flight in 2021.</p><span class="marker MOD2 mod-inline"></span> <span class="marker PREMOD3 mod-inline"></span><p class="topic-paragraph">Twenty-one space fliers—4 Russian cosmonauts and 17 American astronauts—have died during <a href="https://www.britannica.com/science/spaceflight" class="md-crosslink autoxref " data-show-preview="true">spaceflight</a> activities. In January 1967 a three-man crew <a class="md-dictionary-link md-dictionary-tt-off eb" data-term="perished" href="https://www.britannica.com/dictionary/perished" data-type="EB">perished</a> during a ground test of the first <a href="https://www.britannica.com/science/Apollo-space-program" class="md-crosslink autoxref " data-show-preview="true">Apollo</a> spacecraft; in April 1967 and June 1971, first one and then three cosmonauts died during reentry of their <a href="https://www.britannica.com/technology/Soyuz" class="md-crosslink " data-show-preview="true">Soyuz</a> vehicles; in January 1986 an entire seven-member crew died when the U.S. space shuttle <a href="https://www.britannica.com/event/Challenger-disaster" class="md-crosslink " data-show-preview="true"><em>Challenger</em> exploded</a> shortly after launch; and in February 2003 seven more astronauts were lost when the shuttle <a href="https://www.britannica.com/event/Columbia-disaster" class="md-crosslink " data-show-preview="true"><em>Columbia</em> broke up</a> on reentry.</p><span class="marker MOD3 mod-inline"></span> <span class="marker PREMOD4 mod-inline"></span><div class="assemblies"><div class="w-100"><figure class="md-assembly m-0 mb-md-0 card card-borderless print-false" data-assembly-id="100199" data-asm-type="image"><div class="md-assembly-wrapper card-media" data-type="image"><a href="https://cdn.britannica.com/08/76508-050-C956D392/John-H-Glenn-Jr-Friendship-7-launch-Feb-20-1962.jpg" class="gtm-assembly-link position-relative d-flex align-items-center justify-content-center media-overlay-link card-media" data-href="/media/1/40000/100199"><picture><source media="(min-width: 680px)" srcset="https://cdn.britannica.com/08/76508-050-C956D392/John-H-Glenn-Jr-Friendship-7-launch-Feb-20-1962.jpg?w=300"><img src="https://cdn.britannica.com/08/76508-050-C956D392/John-H-Glenn-Jr-Friendship-7-launch-Feb-20-1962.jpg?w=300" alt="John Glenn entering Friendship 7" data-width="1600" data-height="1129" loading="eager"></picture><button class="magnifying-glass btn btn-circle position-absolute shadow btn-white top-10 right-10" aria-label="Zoom in"><em class="material-icons link-blue" data-icon="zoom_in"></em></button></a></div><figcaption class="card-body"><div class="md-assembly-caption text-muted font-14 font-serif line-clamp"><span><a class="gtm-assembly-link md-assembly-title font-weight-bold d-inline font-sans-serif mr-5 media-overlay-link" href="https://cdn.britannica.com/08/76508-050-C956D392/John-H-Glenn-Jr-Friendship-7-launch-Feb-20-1962.jpg" data-href="/media/1/40000/100199">John Glenn entering Friendship 7</a><span>Astronaut John H. Glenn, Jr., entering his Mercury spacecraft Friendship 7 prior to launch of the first U.S. manned Earth orbital mission, February 20, 1962.</span><button class="js-more-btn d-none btn btn-unstyled font-12 bg-white js-content" aria-label="Toggle more/less fact data"><span class="link-blue">(more)</span></button></span></div></figcaption></figure></div></div><p class="topic-paragraph">The first seven U.S. astronauts were chosen for Project <span id="ref943327"></span><a href="https://www.britannica.com/science/Mercury-space-project" class="md-crosslink " data-show-preview="true">Mercury</a> in April 1959. They were selected from some 500 candidates, all members of the U.S. military. Each candidate was required to have experience as a pilot of high-performance jet aircraft and, because of the cramped conditions inside the Mercury spacecraft, to be no more than 5 feet 11 inches (180 cm) tall and weigh no more than 180 pounds (82 kg). These astronauts were U.S. Air Force Captains <span id="ref1270945"></span><a href="https://www.britannica.com/biography/Gordon-Cooper" class="md-crosslink " data-show-preview="true">L. Gordon Cooper, Jr.</a>, <span id="ref1270946"></span><a href="https://www.britannica.com/biography/Virgil-I-Grissom" class="md-crosslink " data-show-preview="true">Virgil (“Gus”) Grissom</a>, and <span id="ref1270947"></span><a href="https://www.britannica.com/biography/Donald-Kent-Slayton" class="md-crosslink " data-show-preview="true">Donald (“Deke”) Slayton</a>; Marine Lieutenant Colonel <a href="https://www.britannica.com/biography/John-Glenn" class="md-crosslink " data-show-preview="true">John H. Glenn, Jr.</a>; and Navy Lieutenant <span id="ref1270948"></span><a href="https://www.britannica.com/biography/Scott-Carpenter" class="md-crosslink " data-show-preview="true">M. Scott Carpenter</a> and Lieutenant Commanders <span id="ref1270949"></span><a href="https://www.britannica.com/biography/Wally-Schirra" class="md-crosslink " data-show-preview="true">Walter M. Schirra, Jr.</a>, and <span id="ref1270950"></span><a href="https://www.britannica.com/biography/Alan-B-Shepard-Jr" class="md-crosslink " data-show-preview="true">Alan B. Shepard, Jr.</a> On May 5, 1961, Alan Shepard made a brief suborbital flight, becoming the first U.S. astronaut to go into space. John Glenn became the first American in orbit with his February 20, 1962, three-orbit flight.</p><span class="marker MOD4 mod-inline"></span> <span class="marker PREMOD5 mod-inline"></span><div class="assemblies"><div class="w-100"><figure class="md-assembly m-0 mb-md-0 card card-borderless print-false" data-assembly-id="112294" data-asm-type="image"><div class="md-assembly-wrapper card-media" data-type="image"><a href="https://cdn.britannica.com/22/115022-050-FA9D6901/Yury-Alekseyevich-Gagarin-1961.jpg" class="gtm-assembly-link position-relative d-flex align-items-center justify-content-center media-overlay-link card-media" data-href="/media/1/40000/112294"><picture><source media="(min-width: 680px)" srcset="https://cdn.britannica.com/22/115022-050-FA9D6901/Yury-Alekseyevich-Gagarin-1961.jpg?w=300"><img src="https://cdn.britannica.com/22/115022-050-FA9D6901/Yury-Alekseyevich-Gagarin-1961.jpg?w=300" alt="Yuri Gagarin" data-width="1536" data-height="1387" loading="eager"></picture><button class="magnifying-glass btn btn-circle position-absolute shadow btn-white top-10 right-10" aria-label="Zoom in"><em class="material-icons link-blue" data-icon="zoom_in"></em></button></a></div><figcaption class="card-body"><div class="md-assembly-caption text-muted font-14 font-serif line-clamp"><span><a class="gtm-assembly-link md-assembly-title font-weight-bold d-inline font-sans-serif mr-5 media-overlay-link" href="https://cdn.britannica.com/22/115022-050-FA9D6901/Yury-Alekseyevich-Gagarin-1961.jpg" data-href="/media/1/40000/112294">Yuri Gagarin</a><span>Yuri Alekseyevich Gagarin, 1961.</span><button class="js-more-btn d-none btn btn-unstyled font-12 bg-white js-content" aria-label="Toggle more/less fact data"><span class="link-blue">(more)</span></button></span></div></figcaption></figure></div></div><p class="topic-paragraph">The Soviet Union selected 20 <a href="https://www.britannica.com/topic/air-force" class="md-crosslink autoxref " data-show-preview="true">air force</a> pilots from 102 candidates for cosmonaut training in February 1960. These individuals also had to meet restrictions on height (170 cm, or 5 feet 7 inches) and weight (70 kg, or 154 pounds) because of the small size of the Soviet Vostok spacecraft. The identity of these individuals was kept secret until they were actually launched into space. Most of the cosmonaut candidates were between 25 and 30 years old and thus did not have the <a class="md-dictionary-link md-dictionary-tt-off eb" data-term="extensive" href="https://www.britannica.com/dictionary/extensive" data-type="EB">extensive</a> test pilot experience of their U.S. counterparts. One of these 20 young men, <a href="https://www.britannica.com/biography/Yuri-Gagarin" class="md-crosslink " data-show-preview="true">Yuri Gagarin</a>, became the first human in space with his April 12, 1961, one-orbit flight.</p><a class="link-module shadow-sm d-block qa-quiz-module" href="/quiz/astronomy-and-space-quiz" data-link-module-iframe-link=""> <img loading="lazy" src="https://cdn.britannica.com/41/155241-131-FB2C633F/View-Andromeda-Galaxy.jpg" alt="View of the Andromeda Galaxy (Messier 31, M31)." class="rounded-sm mr-15" width="70" /> <div class="line-clamp clamp-5"> <div class="module-title bg-green">Britannica Quiz</div> <div class="font-weight-semi-bold mt-5">Astronomy and Space Quiz</div> </div> </a><span class="marker MOD5 mod-inline"></span> <span class="marker PREMOD6 mod-inline"></span><p class="topic-paragraph">In 1997 <span id="ref943333"></span><a href="https://www.britannica.com/place/China" class="md-crosslink " data-show-preview="true">China</a> selected 12 military test pilots, all men, for its first group of taikonaut trainees; the first of these to go up in space, <span id="ref1270951"></span><a href="https://www.britannica.com/biography/Yang-Liwei" class="md-crosslink " data-show-preview="true">Yang Liwei</a>, made a 14-orbit flight in October 2003 on Shenzhou 5.</p><span class="marker MOD6 mod-inline"></span> <span class="marker PREMOD7 mod-inline"></span><p class="topic-paragraph"><a href="https://www.britannica.com/place/India" class="md-crosslink autoxref " data-show-preview="true">India</a> selected four astronauts, pilots in the Indian Air Force, for the <a href="https://www.britannica.com/topic/Gaganyaan" class="md-crosslink " data-show-preview="true">Gaganyaan</a> program, which is scheduled to have its first crewed flight in 2024. The astronauts did the first part of their training in Russia in early 2020 and the remainder at the <a href="https://www.britannica.com/topic/Indian-Space-Research-Organisation" class="md-crosslink " data-show-preview="true">Indian Space Research Organisation</a>’s astronaut training facility in Bengaluru.</p><div class="module-spacing"> <DIV class="marketing-INLINE_SUBSCRIPTION marketing-content" data-marketing-id="INLINE_SUBSCRIPTION"><style> .student-promo-banner-wrapper { container-type: inline-size; margin-bottom: 15px; } @container (min-width: 475px) { .student-promo-banner { flex-direction: row; } .student-promo-banner-img-wrapper { margin-bottom: 0; margin-right: 10px; justify-content: flex-start; } .student-promo-banner-text-wrapper { text-align: left; margin-bottom: 0px; margin-left: 10px; } .student-promo-banner-button-wrapper { margin-right: 0; } }</style> <div class="student-promo-banner-wrapper"> <div class="student-promo-banner d-flex flex-column align-items-center bg-blue rounded p-20"> <div class="student-promo-banner-img-wrapper mb-20 mr-0 d-flex justify-content-center"> <img class="rounded" style="max-width: 100px; min-width: 80px" src="https://cdn.britannica.com/marketing/BlueThistle.webp" /> </div> <div class="student-promo-banner-text-wrapper ml-0 mb-10 text-center text-white"> <div class="h2 mb-10">Get Unlimited Access</div> <div class="h4 font-weight-semi-bold">Try Britannica Premium for free and discover more.</div> </div> <div class="student-promo-banner-button-wrapper d-flex justify-content-center align-items-center ml-auto mr-auto"> <a class="btn btn-m btn-orange" href="https://premium.britannica.com/premium-membership/?utm_source=premium&utm_medium=inline-cta&utm_campaign=august-2024">Subscribe</a> </div> </div> </div> </DIV></div><span class="marker MOD7 mod-inline"></span> <span class="marker PREMOD8 mod-inline"></span><div class="assemblies multiple medialist slider js-slider position-relative d-inline-flex align-items-center mw-100" data-type="other"><div class="slider-container js-slider-container overflow-hidden d-flex"><div class="rw-track d-flex align-items-center"><div class="position-relative rw-slide col-100 px-20 "><figure class="md-assembly m-0 mb-md-0 card card-borderless print-false" data-assembly-id="100281" data-asm-type="image"><div class="md-assembly-wrapper card-media" data-type="image"><a href="https://cdn.britannica.com/54/8354-050-B6B3B6EA/Valentina-Tereshkova-space-orbit-spacecraft-Vostok-6-June-1963.jpg" class="gtm-assembly-link position-relative d-flex align-items-center justify-content-center media-overlay-link card-media" data-href="/media/1/40000/100281"><picture><source media="(min-width: 680px)" srcset="https://cdn.britannica.com/54/8354-050-B6B3B6EA/Valentina-Tereshkova-space-orbit-spacecraft-Vostok-6-June-1963.jpg?w=300"><img src="https://cdn.britannica.com/54/8354-050-B6B3B6EA/Valentina-Tereshkova-space-orbit-spacecraft-Vostok-6-June-1963.jpg?w=300" alt="Valentina Tereshkova" data-width="1600" data-height="1045" loading="eager"></picture><div class="position-absolute top-10 left-10 assembly-slide-tag rounded-lg">1 of 2</div><button class="magnifying-glass btn btn-circle position-absolute shadow btn-white top-10 right-10" aria-label="Zoom in"><em class="material-icons link-blue" data-icon="zoom_in"></em></button></a></div><figcaption class="card-body"><div class="md-assembly-caption text-muted font-14 font-serif line-clamp"><span><a class="gtm-assembly-link md-assembly-title font-weight-bold d-inline font-sans-serif mr-5 media-overlay-link" href="https://cdn.britannica.com/54/8354-050-B6B3B6EA/Valentina-Tereshkova-space-orbit-spacecraft-Vostok-6-June-1963.jpg" data-href="/media/1/40000/100281">Valentina Tereshkova</a><span>Valentina Tereshkova, the first female astronaut to fly into space. She spent nearly three days in orbit aboard the Soviet spacecraft Vostok 6 in June 1963.</span><button class="js-more-btn d-none btn btn-unstyled font-12 bg-white js-content" aria-label="Toggle more/less fact data"><span class="link-blue">(more)</span></button></span></div></figcaption></figure></div><div class="position-relative rw-slide col-100 px-20 "><figure class="md-assembly m-0 mb-md-0 card card-borderless print-false" data-assembly-id="100201" data-asm-type="image"><div class="md-assembly-wrapper card-media" data-type="image"><a href="https://cdn.britannica.com/21/21521-050-02D43180/Sally-Ride-Challenger-space-flight-June-1983.jpg" class="gtm-assembly-link position-relative d-flex align-items-center justify-content-center media-overlay-link card-media" data-href="/media/1/40000/100201"><picture><source media="(min-width: 680px)" srcset="https://cdn.britannica.com/21/21521-050-02D43180/Sally-Ride-Challenger-space-flight-June-1983.jpg?w=300"><img src="https://cdn.britannica.com/21/21521-050-02D43180/Sally-Ride-Challenger-space-flight-June-1983.jpg?w=300" alt="Sally Ride" data-width="1600" data-height="1085" loading="eager"></picture><div class="position-absolute top-10 left-10 assembly-slide-tag rounded-lg">2 of 2</div><button class="magnifying-glass btn btn-circle position-absolute shadow btn-white top-10 right-10" aria-label="Zoom in"><em class="material-icons link-blue" data-icon="zoom_in"></em></button></a></div><figcaption class="card-body"><div class="md-assembly-caption text-muted font-14 font-serif line-clamp"><span><a class="gtm-assembly-link md-assembly-title font-weight-bold d-inline font-sans-serif mr-5 media-overlay-link" href="https://cdn.britannica.com/21/21521-050-02D43180/Sally-Ride-Challenger-space-flight-June-1983.jpg" data-href="/media/1/40000/100201">Sally Ride</a><span>Sally Ride, the first U.S. female astronaut to fly into space, aboard the space shuttle Challenger during her maiden flight in June 1983.</span><button class="js-more-btn d-none btn btn-unstyled font-12 bg-white js-content" aria-label="Toggle more/less fact data"><span class="link-blue">(more)</span></button></span></div></figcaption></figure></div></div></div><button disabled="true" class="prev-button js-prev-button position-absolute btn btn-circle shadow btn-lg btn-blue-dark m-20"><span class="material-icons" data-icon="keyboard_arrow_left"></span></button><button disabled="true" class="next-button js-next-button position-absolute btn btn-circle shadow btn-lg btn-blue-dark m-20"><span class="material-icons" data-icon="keyboard_arrow_right"></span></button></div><p class="topic-paragraph">In both the United States and the Soviet Union, no <span id="ref943334"></span><a href="https://www.britannica.com/topic/women" class="md-crosslink ">women</a> were initially selected as astronauts. (In the United States, 13 women, the “Mercury 13,” underwent some of the same testing as the seven Mercury astronauts. Wally Funk, who later became the oldest person in space in 2021, was among them.) In 1962 the Soviet Union chose five women as cosmonaut trainees; one of them, <span id="ref1270952"></span><a href="https://www.britannica.com/biography/Valentina-Tereshkova" class="md-crosslink " data-show-preview="true">Valentina Tereshkova</a>, went into orbit in June 1963, becoming the first woman in space. The United States did not select women for astronaut training until 1978, and the first female U.S. astronaut, <span id="ref1270953"></span><a href="https://www.britannica.com/biography/Sally-Ride" class="md-crosslink " data-show-preview="true">Sally Ride</a>, was launched aboard the <a href="https://www.britannica.com/technology/space-shuttle" class="md-crosslink " data-show-preview="true">space shuttle</a> <em>Challenger</em> in June 1983. China selected two women in its second group of taikonaut trainees in 2010, and the first to fly in to space was <span id="ref1283968"></span><a href="https://www.britannica.com/biography/Liu-Yang" class="md-crosslink " data-show-preview="true">Liu Yang</a> on Shenzhou 9 in June 2012.</p><span class="marker MOD8 mod-inline"></span> <span class="marker PREMOD9 mod-inline"></span><p class="topic-paragraph">The United States selected only pilots as astronauts until 1965, when six scientists with technical or medical degrees were chosen for astronaut training. One of them, geologist <span id="ref1270954"></span><a href="https://www.britannica.com/biography/Harrison-Schmitt" class="md-crosslink " data-show-preview="true">Harrison (“Jack”) Schmitt</a>, became a crew member of <a href="https://www.britannica.com/event/Apollo-17" class="md-crosslink autoxref " data-show-preview="true">Apollo 17</a>, the final Apollo mission to the Moon, in December 1972.</p><div class="one-good-fact-module"> </div><span class="marker MOD9 mod-inline"></span> <span class="marker PREMOD10 mod-inline"></span><p class="topic-paragraph">All told, 24 astronauts (all Americans) have <a href="https://www.britannica.com/story/how-many-people-have-been-to-the-moon" class="md-crosslink " data-show-preview="true">gone to the Moon</a>, and 12 of them walked on its surface. As part of the <a href="https://www.britannica.com/topic/Artemis-program" class="md-crosslink " data-show-preview="true">Artemis</a> space program, launched in 2017, <a href="https://www.britannica.com/topic/NASA" class="md-crosslink " data-show-preview="true">NASA</a> aims to return astronauts to the Moon by 2025, with the goal of establishing a <a class="md-dictionary-link md-dictionary-tt-off eb" data-term="sustainable" href="https://www.britannica.com/dictionary/sustainable" data-type="EB">sustainable</a> presence there and on other planets. The program also seeks to land the first woman and first person of colour on the Moon, and that woman may be <a href="https://www.britannica.com/story/7-questions-for-astronaut-jessica-meir" class="md-crosslink " data-show-preview="true">Jessica Meir</a>.</p><span class="marker MOD10 mod-inline"></span> </section> <span class="marker end-of-content"></span><span class="marker after-article"></span></div> <div id="chatbot-simplify-root"></div> <div id="chatbot-root"></div> </div> </div> </div> <div class="ai-dialog-placeholder"></div> </div> </div> <aside class="col-md-da-320"></aside> </div> </div> </div> </div> </article> </div> </div> </div> </div> </main> <div id="md-footer"></div> <noscript><iframe src="//www.googletagmanager.com/ns.html?id=GTM-5W6NC8" height="0" width="0" style="display:none;visibility:hidden"></iframe></noscript>  <script> window.ap3c = window.ap3c || {}; var ap3c = window.ap3c; ap3c.cmd = ap3c.cmd || []; ap3c.cmd.push(function() { ap3c.init('ZO4siT4cLwnykPnzZWJtd3Byb2Q', 'https://engage.email.britannica.com/'); ap3c.track({v: 0}); }); ap3c.activity = function(act) { ap3c.act = (ap3c.act || []); ap3c.act.push(act); }; var s, t; s = document.createElement('script'); s.type = 'text/javascript'; s.src = "https://engage.email.britannica.com/app.js"; t = document.getElementsByTagName('script')[0]; t.parentNode.insertBefore(s, t); </script> <script class="marketing-page-info" type="application/json"> {"pageType":"Topic","templateName":"DESKTOP","pageNumber":1,"pagesTotal":3,"pageId":40000,"pageLength":982,"initialLoad":true,"lastPageOfScroll":false} </script> <script class="marketing-content-info" type="application/json"> [] </script> <script src="https://cdn.britannica.com/mendel-resources/3-133/js/libs/jquery-3.5.0.min.js?v=3.133.48"></script> <script type="text/javascript" data-type="Init Mendel Code Splitting"> (function() { $.ajax({ dataType: 'script', cache: true, url: 'https://cdn.britannica.com/mendel-resources/3-133/dist/topic-page.js?v=3.133.48' }); })(); </script> <script class="analytics-metadata" type="application/json"> {"leg":"A","adLeg":"A","userType":"ANONYMOUS","pageType":"Topic","pageSubtype":null,"articleTemplateType":"PAGINATED","gisted":false,"pageNumber":1,"hasSummarizeButton":false,"hasAskButton":true,"hasAiTopQuestions":false,"hasSimplifyButton":false} </script> <script type="text/javascript"> EBStat={accountId:-1,hostnameOverride:'webstats.eb.com',domain:'www.britannica.com', json:''}; </script> <script type="text/javascript"> ( function() { $.ajax( { dataType: 'script', cache: true, url: '//www.britannica.com/webstats/mendelstats.js?v=1' } ) .done( function() { try {writeStat(null,EBStat);} catch(err){} } ); })(); </script> <div id="bc-fixed-dialogue"></div> </body> </html>

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Astronaut | Definition, Facts, & Training | Britannica