Related by context. Frequent words. (Click for all words.) 68 XMM Newton 63 extrasolar planets 63 exoplanets 63 extrasolar planet 62 GOCE 61 astronomers 61 Very Large Telescope 61 THEMIS 61 HD #b [002] 60 planet orbiting 60 NASA Cassini spacecraft 59 JWST 59 Cassini 59 HiRISE 59 Saturn rings 59 brown dwarfs 59 exoplanet 58 Spitzer Space Telescope 58 planets orbiting 58 ringed planet 58 Cassini spacecraft 58 distant galaxies 58 Corot 58 telescope 58 Huygens 58 MESSENGER 58 Planck 57 gamma ray burst 57 CryoSat 57 WMAP 57 cosmic microwave background 57 Space Agency 57 outer planets 57 unaided eye 57 distant galaxy 57 GLAST 57 orbiting 57 Mars Reconnaissance Orbiter 57 rocky planets 57 Space Telescope 57 spacecraft 57 Milky Way Galaxy 57 planets 57 redshift 57 Chandrayaan 57 gamma ray bursts 57 LCROSS 56 adaptive optics 56 interferometer 56 Saturn moon 56 brown dwarf 56 optical telescopes 56 Envisat 56 Kepler 56 terrestrial planets 56 Gliese 56 comet Wild 56 comet 56 galaxy cluster 56 astrophysicists 56 occultation 56 Itokawa 56 Lunar Reconnaissance Orbiter 56 gravitational lensing 55 cosmic ray 55 STEREO 55 gravitational waves 55 orbits 55 celestial objects 55 supernovae 55 Hubble Telescope 55 quasars 55 JAXA 55 cosmic rays 55 Sedna 55 Solar System 55 Lunar Crater Observation 54 lunar surface 54 pulsar 54 globular clusters 54 flyby 54 telescopes 54 WM Keck Observatory 54 spectroscopic 54 Astronomers 54 cometary 54 Hubble 54 Betelgeuse 54 Hubble telescope 54 Phobos 54 moon Titan 53 LRO 53 quasar 53 lunar orbit 53 circular orbit 53 supernova explosion 53 X ray Observatory 53 Spectrometer 53 Hubble Space Telescope 53 infrared wavelengths 53 Martian surface