Related by context. Frequent words. (Click for all words.) 68 planets orbiting 66 brown dwarfs 64 planet orbiting 64 rocky planets 64 exoplanets 63 HD #b [002] 63 brown dwarf 62 extrasolar planets 62 Gliese 61 supernovae 61 extrasolar planet 60 supernovas 60 distant galaxy 60 exoplanet 60 globular clusters 60 elliptical galaxies 59 dwarf galaxies 59 XMM Newton 58 gamma ray burst 58 planets 57 terrestrial planets 57 galaxies 57 quasars 56 quasar 56 nebulae 56 celestial objects 55 distant galaxies 55 galaxy cluster 55 spiral galaxies 55 supernova 55 gamma ray bursts 55 astronomers 55 Milky Way galaxy 55 pulsars 55 Saturn moons 54 Milky Way Galaxy 54 Betelgeuse 54 Alpha Centauri 54 neutron star 54 Astronomers 54 orbits 54 supernova explosion 53 galaxy clusters 53 Spitzer Space Telescope 53 X ray Observatory 53 moons 53 astrophysicists 53 Earth asteroids 53 unaided eye 53 Saturn rings 52 ringed planet 52 Sedna 52 orbiting 52 outer planets 52 pulsar 52 galaxy 52 Cassini spacecraft 52 positrons 52 neutron stars 52 comets 51 comet 51 Saturn moon 51 supermassive black holes 51 infrared wavelengths 51 asteroid 51 NASA Cassini spacecraft 51 asteroids 51 astrophysical 51 nebula 51 cosmic rays 51 redshift 50 NASA Chandra 50 gamma rays 50 supermassive black hole 50 interstellar dust 50 Enceladus 50 gravitational waves 49 WM Keck Observatory 49 spectroscopic 49 neutrino 48 cosmic ray 48 CMEs 48 celestial bodies 48 suns 48 Milky Way 48 Hubble Telescope 48 neutrinos 48 spiral galaxy 48 habitable zone 48 chemical composition 48 interstellar medium 48 Very Large Telescope 48 solar flares 47 Cassini 47 auroras 47 fainter 47 Martian surface 47 Jupiter Saturn Uranus 47 corona 47 sunspot 47 Chandra X ray