Related by context. Frequent words. (Click for all words.) 57 astronaut 52 Metcalf Lindenburger 51 NASA Astronaut 50 NASA astronaut 50 NASA astronaut corps 47 spaceflight 46 Mercury Gemini 46 Yang Liwei 45 Women Airforce Service 45 Alan Shepard 45 astronaut Buzz Aldrin 45 Piers Sellers 45 June Scobee Rodgers 45 Tuskegee Airman 45 Astronaut 44 Soviet cosmonaut Yuri Gagarin 44 Mike Melvill 44 Chuck Yeager 44 Tombaugh 44 NASA 44 space shuttle 44 spaceflights 44 Astronaut Buzz Aldrin 43 Apollo lunar 43 Naval aviator 43 spacecraft 43 Wernher von Braun 43 Sally Ride 43 Eileen Collins 43 sub orbital 43 Apollo astronauts 43 astronaut corps 42 Christa McAuliffe backup 42 Hobaugh 42 teacher Christa McAuliffe 42 Russian cosmonaut Yuri Malenchenko 42 Cernan 42 administrator Sean O'Keefe 42 Israeli astronaut Ilan 42 astronauts 42 Anousheh Ansari 42 Amelia Earhart 42 cosmonaut 41 aviators 41 SpaceX Falcon 9 41 Buzz Aldrin 41 William Oefelein 41 Shuttle commander 41 orbit 41 astronaut Peggy Whitson 41 fighter pilot 41 spaceplane 41 spaceship 41 Nicole Stott 41 aviator Amelia Earhart 41 Tom Skerritt 41 Edwin Buzz Aldrin 41 Right Stuff 41 Eric Boe 41 Shuttle astronauts 40 astronaut Yang Liwei 40 De Winne 40 aviator 40 Peggy Whitson 40 Bigelow 40 crewmates 40 Shepard 40 Yuri Gagarin 40 suborbital flight 40 naval aviator 40 Readdy 40 Naval Academy graduate 40 Retired Brig 40 Burt Rutan 39 suborbital flights 39 Gene Roddenberry 39 Space Shuttle Endeavour 39 Sturckow 39 Hickam 39 manned spaceflight 39 shuttle missions 39 Jimmy Doolittle 39 Julie Payette 39 NASA Administrator 39 Professor Hawking 39 SpaceShipOne 39 Gagarin flight 39 Cosmonauts 39 Kalpana Chawla 39 Nie Haisheng 39 Commander Eileen 39 Richard Feynman 39 Space Shuttle 39 Caldwell Dyson 39 astronaut Julie Payette 39 Leland Melvin 39 Tuskegee Institute 39 robotic spacecraft 39 manned spacecraft 39 PSLV C# 39 Mars Pathfinder