Related by context. Frequent words. (Click for all words.) 55 heat shield 53 orbital debris 53 orbiter 49 spacecraft 49 meteorites 48 insulating foam 48 thermal tiles 48 asteroid 47 shuttle Discovery 47 comet 46 orbiters 45 cosmic radiation 45 meteorite 45 liftoff 45 comets 45 foam insulation 45 orbiting 44 space shuttle Discovery 44 thermal tile 44 solar flares 44 shuttle 43 magnetosphere 43 space shuttle 43 asteroids 43 Saturn moon 43 Martian surface 43 Gerstenmaier 43 Apophis 43 LCROSS 43 lunar surface 42 meteor 42 Tempel 1 42 rocky planets 42 aboard Endeavour 42 gravitational waves 42 cosmic rays 42 NASA 42 cosmic microwave background 41 Saturn rings 41 debris 41 orbit 41 shuttle Atlantis 41 Space Shuttle Discovery 41 planets 41 gamma ray burst 41 Earth orbit 41 JAXA 41 Space Shuttle Endeavour 40 Astronomers 40 planets orbiting 40 shuttle missions 40 undocking 40 outer space 40 payload bay 40 Nasa 40 Space Shuttle Atlantis 40 Columbia Accident Investigation 39 Meridiani Planum 39 Hubble 39 craters 39 Martian soil 39 impactor 39 gap fillers 39 exoplanets 39 Enceladus 39 extrasolar planets 39 asteroid belt 39 Red Planet 39 Asteroid 39 Endeavour 39 gamma rays 39 Hubble Space Telescope 39 spaceship 38 hydrazine 38 International Space Station 38 Soyuz capsule 38 lunar orbit 38 Shuttle Endeavour 38 blunt trauma 38 Gusev Crater 38 Discovery astronauts 38 astronauts 38 lander 38 Space shuttle Atlantis 38 Spitzer Space Telescope 38 Cassini spacecraft 38 Space shuttle Discovery 38 gamma ray bursts 38 Martian atmosphere 38 Space Agency 38 Orbiter 38 projectile 38 space shuttle Atlantis 38 organic molecules 38 flyby 38 Atlantis astronauts 38 Dittemore 38 Hubble telescope 37 ionosphere 37 orbiting lab 37 exoplanet