Related by context. Frequent words. (Click for all words.) 70 satellites 65 geostationary satellites 65 orbiting satellites 61 GPS satellites 59 satellite 58 remote sensing satellites 57 optical telescopes 57 orbiters 57 orbiting spacecraft 56 spy satellites 56 orbiting 56 reconnaissance satellites 55 spacecraft 54 orbiting Mars 53 Iridium satellite 53 spacecrafts 52 satellite constellation 52 geostationary 52 Mars Odyssey 52 positioning satellites 51 observatories 51 Global Surveyor 51 antennas 50 geosynchronous orbit 50 infrared telescope 50 geostationary orbit 50 rovers 49 orbits 49 telescopes 49 radars 49 robotic spacecraft 49 orbited 49 orbiting telescope 49 orbiter 49 Mars rovers 48 Orbiting 48 unmanned spacecraft 48 Cassini Huygens 48 lander 48 orbit 47 NASA Mars Odyssey 47 seismographs 47 COROT 47 thermal emission spectrometer 47 CloudSat 47 Stardust spacecraft 47 remote sensing satellite 47 telescope 47 asteroids 47 Satellites 47 Apophis 46 Jodrell Bank 46 intercontinental ballistic missiles 46 THEMIS 46 Phoenix Mars lander 46 transmitters 46 astronomical observations 46 meteoroids 46 Cassini orbiter 46 synthetic aperture radar 46 antennae 46 ionosphere 46 lunar surface 45 rover 45 Global Positioning System 45 microsatellites 45 Cassini spacecraft 45 ICBMs 45 electromagnetic waves 45 Lunar Reconnaissance Orbiter 45 polar orbit 45 infrared wavelengths 45 Hubble Telescope 45 astronomical objects 45 Radarsat 2 45 HD #b [002] 45 transponders 45 celestial bodies 45 Earth asteroids 45 QuikScat 44 comet nucleus 44 celestial objects 44 Satellite 44 sensor nodes 44 remote sensing 44 twin rovers 44 drones 44 Very Large Array 44 Cassini 44 NEOs 44 observatory 44 satcom 44 atomic clocks 44 asteroid 44 NASA Kepler 44 NASA Cassini spacecraft 44 sonars 44 orbital 44 orbiting observatory 44 martian 44 New Horizons spacecraft