Related by context. Frequent words. (Click for all words.) 70 teacher Christa McAuliffe 66 Christa McAuliffe 55 astronaut 55 shuttle Challenger 53 space shuttle 51 Challenger exploded 50 NASA astronaut 49 astronauts 48 astronaut corps 48 June Scobee Rodgers 48 shuttle Endeavour 48 shuttle Discovery 48 Ilan Ramon 47 Kalpana Chawla 47 McAuliffe 46 Hubble servicing 46 space shuttle Endeavour 46 Orion capsule 46 space shuttle Atlantis 45 Caldwell Dyson 45 shuttle fleet 45 Orion spacecraft 45 spaceflight 44 Ares rocket 44 Astronaut 44 Soyuz capsule 44 Dennis Tito 44 NASA 44 shuttle 44 shuttle Atlantis 44 astronauts aboard 44 spacewalkers 44 International Space Station 44 shuttle missions 43 Russian Soyuz spacecraft 43 space shuttle Discovery 43 aboard Endeavour 43 Discovery astronauts 43 Yuri Gagarin 43 Mission Specialists 43 Alan Shepard 43 Tracy Caldwell Dyson 43 NASA Astronaut 43 Megan McArthur 43 Heidemarie Stefanyshyn Piper 43 Nicole Stott 42 Stefanyshyn Piper 42 Gregory Chamitoff 42 Shuttle astronauts 42 thermal tile 42 Lee Archambault 42 Discovery payload bay 42 spacewalk 42 Shuttle Discovery 42 Anousheh Ansari 42 Peggy Whitson 42 Piers Sellers 42 spaceship 42 spacewalking astronaut 42 liftoff 41 Space shuttle Atlantis 41 Atlantis astronauts 41 Russian Soyuz rocket 41 Spacewalking astronauts 41 spaceflights 41 Rick Mastracchio 41 Space Shuttle Endeavour 41 orbiting complex 41 field Infrared Survey 41 Commander Eileen 41 Endeavour 41 orbiting laboratory 41 orbiting observatory 41 shuttle astronauts 41 Daniel Tani 41 Robert Behnken 41 Japan Kibo lab 41 spacecraft 41 Orbiting Carbon Observatory 41 Space Shuttle Atlantis 41 Shuttle Endeavour 41 Space Shuttle Discovery 40 Frank De Winne 40 Columbia Accident Investigation 40 Marcia Dunn 40 Cape Canaveral Fla. 40 orbiting telescope 40 manned spaceflight 40 Apollo astronauts 40 Space shuttle Endeavour 40 Space Shuttle Columbia 40 Dragon capsule 40 Challenger Learning 40 Mercury Gemini 40 Yurchikhin 40 Gerstenmaier 40 astronaut Sunita Williams 40 unmanned spacecraft 40 shuttle disintegrated 40 Mikhail Kornienko 39 Nasa