Related by context. Frequent words. (Click for all words.) 51 orbit 51 spacecraft 50 orbiting 46 orbiter 45 orbits 44 thrusters 43 lunar orbit 43 orbited 43 Flight controllers 42 orbital 41 elliptical orbit 41 polar orbit 41 Earth orbit 41 spacewalkers 41 NASA 40 International Space Station 40 JAXA 40 orbiting outpost 40 thruster 40 liftoff 40 orbiters 40 Atlantis astronauts 39 Hayabusa 39 orbiting laboratory 39 lander 39 observatory 39 Space Shuttle Columbia 39 space shuttle Discovery 39 space shuttle Atlantis 38 unmanned spacecraft 38 Nasa 38 astronauts 38 lunar surface 38 shuttle 38 mission 38 Malenchenko 38 Shuttle Atlantis 38 shuttle Atlantis 37 Soyuz capsule 37 astronauts aboard 37 cosmonauts 37 Space Shuttle Atlantis 37 Phoenix Mars Lander 37 Mission Control 37 spaceship 36 celestial bodies 36 Red Planet 36 Yurchikhin 36 space shuttle Endeavour 36 ISS 36 Cassini 36 geostationary orbit 36 orbiting satellites 36 Space Shuttle Discovery 36 Atlantis 36 spacemen 36 astronaut 36 shuttle Discovery 36 Padalka 36 cosmonaut 35 blastoff 35 Huygens 35 commander Rick Sturckow 35 undocked 35 asteroid 35 space shuttle 35 Discovery astronauts 35 manned spacecraft 35 Cassini spacecraft 35 Shuttle Endeavour 35 LCROSS 35 orbital outpost 35 Endeavour astronauts 35 moon 35 Soyuz spacecraft 34 undock 34 Space shuttle Discovery 34 Shuttle Discovery 34 Hubble telescope 34 Spacecraft 34 crewmates 34 crewmembers 34 Hubble 34 Endeavour 34 spacewalk 34 heat shield 34 NASA Administrator 34 comet 34 Fuglesang 34 Soyuz 34 Russian cosmonauts 34 Feustel 34 Space Shuttle Endeavour 34 orbital debris 34 shuttle Endeavour 34 rover 34 Chandrayaan 33 Hubble Space Telescope 33 Martian atmosphere 33 Mars Odyssey 33 reentry