Related by context. Frequent words. (Click for all words.) 76 spacecraft 75 orbits 73 Earth orbit 73 orbiting 66 orbiter 66 orbited 64 orbital 61 International Space Station 59 Soyuz 58 Soyuz spacecraft 58 astronauts 56 lunar probe 56 lunar surface 56 orbiting outpost 56 space shuttle Discovery 56 orbiters 56 liftoff 55 satellites 55 shuttle Discovery 55 lander 55 JAXA 55 Baikonur Cosmodrome 55 NASA 54 Space Station 54 Space Agency 54 shuttle Atlantis 54 outer space 54 spaceship 54 ISS 53 Nasa 53 Cassini 53 space shuttle 53 spacewalk 53 thrusters 53 payload 53 shuttle 53 Hubble 53 astronaut 52 Chandrayaan 52 Space shuttle Discovery 52 moon 52 Hubble Space Telescope 52 asteroid 52 Orbiter 51 space shuttle Endeavour 51 Space Shuttle Discovery 51 LCROSS 51 Discovery astronauts 51 flyby 51 Chang'e 51 payloads 51 rover 51 Cape Canaveral 50 Atlas V 50 Russian Soyuz 50 MESSENGER 50 Space shuttle Endeavour 50 Huygens 50 Soyuz TMA 50 lunar 50 Hayabusa 50 space shuttle Atlantis 50 shuttle astronauts 49 cosmonauts 49 comet 49 Ariane 5 49 interplanetary 49 Baikonur cosmodrome 49 Red Planet 49 undocking 49 booster rocket 49 Hubble telescope 49 Cape Canaveral Air Force 49 human spaceflight 48 Martian surface 48 Cassini spacecraft 48 stratosphere 48 spacesuits 48 Spacecraft 48 Fincke 47 shuttle Endeavour 47 shuttle missions 47 spacewalkers 47 spaceflight 47 spacewalks 47 Endeavour 47 Mission Control 47 asteroid belt 47 Gerstenmaier 47 Mars 47 Space shuttle Atlantis 46 space shuttles 46 Atlantis 46 rocket 46 NASA astronaut 46 Cape Canaveral Fla. 46 cosmonaut 46 astronauts aboard 46 Mars Reconnaissance Orbiter 46 launch pad 46 Atlantis astronauts