Related by context. Frequent words. (Click for all words.) 73 extrasolar planets 71 extrasolar planet 71 exoplanets 70 rocky planets 70 planets orbiting 68 exoplanet 67 super Earths 66 planets 66 brown dwarfs 65 COROT 65 NASA Kepler 65 terrestrial planets 65 planet orbiting 62 HD #b [002] 61 astronomers 61 elliptical galaxies 61 distant galaxy 60 magnetar 60 GRBs 60 XMM Newton 60 hot Jupiters 60 brown dwarf 60 Orion Nebula 60 distant galaxies 60 supernovae 60 Saturn moons 59 Astronomers 59 galaxy clusters 59 supernovas 58 pulsars 58 moon Europa 58 globular clusters 58 nebulae 58 Jupiter moons 57 quasars 57 astronomical observations 57 celestial objects 57 galaxies 57 NASA Cassini spacecraft 57 supernova explosions 57 Spitzer Space Telescope 57 Milky Way Galaxy 56 gamma ray bursts 56 Eta Carinae 56 Saturn moon 56 Earth asteroids 56 supernova explosion 56 X ray emission 56 ringed planet 56 X ray Observatory 56 astrophysicists 56 dwarf galaxies 56 interstellar dust 55 unaided eye 55 infrared wavelengths 55 supernova 55 gamma ray burst 55 celestial bodies 55 Milky Way galaxy 55 gravitational lensing 55 dwarf galaxy 54 NASA Chandra 54 outer planets 54 WM Keck Observatory 54 redshift 54 gravitational wave 54 optical telescopes 54 quasar 54 habitable zone 54 gravitational waves 54 organic molecules 54 galaxy 54 comet nucleus 53 Saturn rings 53 occultation 53 galaxy cluster 53 Andromeda Galaxy 53 planetary 53 Geminids 53 Betelgeuse 53 astrophysical 53 asteroids 53 Solar System 53 cosmic rays 52 infrared telescope 52 Gliese 52 nebula 52 Very Large Array 52 Cassini Huygens 52 comets 52 neutrino 52 neutron star 52 spiral galaxies 52 moon Titan 52 auroras 52 cosmic microwave background 52 supernova remnant 52 spectroscopic 52 orbiting 52 interstellar medium 52 equatorial regions