23 Of The Most Important Pictures In The History Of Space Exploration

Soviet cosmonaut Valentina Tereshkova, the first woman in space, exits the Vostok capsule in June 1963.

NASA astronauts Kathryn D. Sullivan (left) and Sally Ride in the Space Shuttle Challenger, showing off their design for a sleeping bag complete with restraints for zero-gravity conditions, 1984.

Mission specialist Judith Resnik sends a message to her father from on board the shuttle Discovery on Aug. 30, 1984.

New Hampshire teacher Christa McAuliffe trains for space aboard NASA’s KC-135 zero-gravity aircraft in 1986.

Christa McAuliffe and fellow crew member Judy Resnik meet members of the media on the launchpad of Cape Canaveral, Florida, on Jan. 8, 1986.

NASA astronaut Jan Davis wears a sign reading “Outer Space Country Kitchen” while eating aboard the shuttle Endeavour on Sept. 12, 1992.

Payload specialist Mamoru Mohri of Japan (left) and mission specialist Mae Jemison of Chicago walk together after arriving with the rest of the STS-47 crew on Sept. 9, 1992, at the Kennedy Space Center in Florida.

NASA astronaut Ellen Ochoa trains for space at Vance Air Force Base in Houston, 1993.

NASA astronaut Kathryn C. Thornton hovers over equipment on the Hubble Space Telescope on Oct. 22, 1993.

NASA astronaut Eileen Collins sits at the pilot’s station in the Space Shuttle Discovery on Feb. 3, 1995. Collins, the first woman space shuttle pilot, is en route to rendezvous with Russia’s Mir space station.

NASA astronaut Tamara Jernigan goes over data aboard the Space Shuttle Endeavour in 1995.

French cosmonaut Claudie Haigneré trains in the Soyuz capsule at Star City, Russia, on Feb, 10, 1996.

NASA astronaut Shannon Lucid shares a laugh with urine samples in her hand, aboard the Russian Mir space station on Sept. 16, 1996.

NASA astronaut Kalpana Chawla looks over a procedures checklist aboard the Space Shuttle Columbia on Jan. 27, 2003.

NASA astronaut Laurel B. Clark participates in a mission training session at the Johnson Space Center on April 25, 2002, in Houston, Texas.

Space tourist Anousheh Ansari takes part in a training session at the Gagarin Cosmonaut Training Center in Star City, Russia, on Sept. 19, 2006.

Astronauts pose for a photo in the International Space Station on April 7, 2010. Pictured clockwise from lower right are American NASA astronauts Stephanie Wilson, Tracy Caldwell Dyson, and Dorothy Metcalf-Lindenburger, as well as Japanese JAXA astronaut Naoko Yamazaki.

China's first woman astronaut Liu Yang before boarding the Shenzhou-9 spacecraft on June 16, 2012.

NASA astronaut Sunita Williams during an extravehicular activity mission on Sept. 5, 2012.

Wearing a gas mask, European Space Agency Italian astronaut Samantha Cristoforetti takes part in a preflight training session at the Gagarin Cosmonaut Training Center in Star City, Russia, on Dec. 11, 2013.

NASA astronaut Jessica Meir participates in water survival training in case of an emergency water landing, in Noginsk, Russia, on April 5, 2018.

NASA astronaut Anne McClain during a spacesuit check before launch on Dec. 3, 2018.

NASA astronaut Christina Hammock Koch trains at the Gagarin Cosmonaut Training Center in Star City, Russia, Feb. 20, 2019.