Related by context. Frequent words. (Click for all words.) 48 Dittemore 47 reconnaissance satellites 47 spacecraft 47 Cassini Huygens 47 satellites 46 alien spacecraft 45 spy satellites 45 NASA 45 satellites orbiting 45 orbiting satellites 45 astronomical observations 44 Global Surveyor 44 orbiting 44 Nasa 44 amateur astronomers 44 orbiting spacecraft 43 Isro 43 orbiter 43 HiRISE 43 Space Agency 43 Cassini 43 Garlasco 43 orbit 42 Tombaugh 42 satellite 42 telescope 42 spacecrafts 42 UFO 42 Piers Sellers 42 Hadow 42 remote sensing satellites 41 NASA Wallops Flight 41 reconnaissance 41 Jupiter moons 41 A'Hearn 41 orbiters 41 X #B 41 XMM Newton 41 Cernan 41 Obering 41 orbiting telescope 41 astronomers 41 ISRO 41 Shostak 41 NASA Kepler 41 satellite imagery 40 Huygens 40 robotic spacecraft 40 optical telescopes 40 CloudSat 40 remotely piloted aircraft 40 Space.com 40 THEMIS 40 Von Braun 40 Spaceflight 40 National Aeronautic 40 orbital 40 UFOs 40 manager Ron Dittemore 40 Earth orbit 40 Stardust spacecraft 40 aerial reconnaissance 40 SIGINT 40 telescopes 40 synthetic aperture radar 40 COROT 39 ScanEagle 39 Schweickart 39 JAXA 39 Squyres 39 reconnaissance missions 39 orbited 39 Orbiter 39 unmanned aerial vehicle 39 LCROSS 39 NASA Cassini spacecraft 39 astrophysicists 39 orbits 39 GPS satellites 39 Shenzhou V 39 extraterrestrials 39 extrasolar planet 39 lunar landing 39 Hubble 38 microsatellites 38 geostationary satellites 38 lander 38 spy 38 flyby 38 Kucharek 38 polar orbit 38 Space Telescope 38 airship 38 amateur astronomer 38 Mars rover 38 lunar surface 38 lidar 38 comet Wild 38 Popovkin 38 skywatchers 38 TRMM