Related by context. Frequent words. (Click for all words.) 60 space shuttle 59 NASA astronaut 56 astronaut 55 shuttle Challenger 52 Soviet cosmonaut Yuri Gagarin 50 NASA Astronaut 49 NASA astronaut corps 49 space shuttles 49 shuttle 49 Space Shuttle Columbia 48 Christa McAuliffe backup 48 NASA 48 Astronaut 48 Space Shuttle 48 Metcalf Lindenburger 48 Space Shuttle Challenger 47 teacher Christa McAuliffe 47 astronauts 46 Space Shuttle Endeavour 45 Eileen Collins 45 astronaut Peggy Whitson 45 spacecraft 45 astronaut Buzz Aldrin 45 shuttle missions 45 shuttle disintegrated 45 Challenger exploded 44 Shuttle Endeavour 44 robotic spacecraft 44 June Scobee Rodgers 44 Commander Peggy Whitson 44 Rick Husband 44 Mars Pathfinder 44 Space Shuttle Discovery 44 NASA Space Shuttle 44 spaceship 44 Sputnik satellite 44 Shuttle commander 44 Dan Tani 43 shuttle fleet 43 manned spacecraft 43 Shuttle Discovery 43 Christa McAuliffe 43 Oleg Skripochka 43 Sean O'Keefe 43 shuttle Discovery 43 Cape Canaveral 43 Ares rocket 43 orbiter 43 Mars Rover 43 astronaut Julie Payette 43 Alan Shepard 43 SpaceX Falcon 9 43 Retired Brig 43 astronaut Daniel Tani 43 Ilan Ramon 42 Yuri Gagarin 42 Sandra Magnus 42 spacecrafts 42 spaceflight 42 Sturckow 42 lunar landing 42 Peggy Whitson 42 Orion capsule 42 naval aviator 42 Shuttle Atlantis 41 spaceflights 41 spaceplane 41 Cernan 41 Koichi Wakata 41 Orion spacecraft 41 orbiters 41 space shuttle Discovery 41 Charles Bolden 41 astronauts aboard 41 human spaceflight 41 Gagarin 41 Piers Sellers 41 Daniel Tani 41 Julie Payette 41 planetary exploration 41 Shuttle astronauts 41 Skylab 41 liftoff 41 Cape Canaveral Fla. 41 congresswoman Gabrielle Giffords 41 Hobaugh 41 Schirra 41 Nicole Stott 41 shuttle Atlantis 41 Eyharts 40 Cape Canaveral Air Force 40 Apollo astronauts 40 astronaut Lisa Nowak 40 International Space Station 40 Yang Liwei 40 Russian leased Baikonur 40 Spacecraft 40 Scott Parazynski 40 Lee Archambault 40 CALIPSO 40 VAFB