Related by context. Frequent words. (Click for all words.) 68 globular clusters 63 galaxies 63 elliptical galaxies 62 Milky Way Galaxy 62 dwarf galaxy 62 Milky Way galaxy 62 Orion Nebula 62 distant galaxy 61 spiral galaxy 61 nebulae 61 quasars 60 supernova explosion 60 galaxy cluster 60 GRBs 60 quasar 60 distant galaxies 59 brown dwarfs 59 X ray emission 59 planets orbiting 59 spiral galaxies 58 planet orbiting 58 Milky Way 57 supernovae 57 nebula 57 rocky planets 57 Betelgeuse 56 brown dwarf 56 galaxy 56 supermassive black holes 56 Spitzer Space Telescope 56 supernova explosions 56 terrestrial planets 56 unaided eye 56 planets 56 gamma ray burst 55 gamma ray bursts 55 neutron stars 55 dwarf galaxies 55 Eta Carinae 54 astronomers 54 HD #b [002] 54 extrasolar planets 54 galaxy clusters 54 super Earths 54 supernova 54 fainter 53 Astronomers 53 XMM Newton 53 Large Magellanic Cloud 53 supermassive black hole 53 hot Jupiters 53 comets 53 pulsars 52 neutron star 52 X ray Observatory 52 extrasolar planet 52 Saturn rings 51 NASA Chandra 51 redshift 51 supernovas 51 exoplanets 51 interstellar dust 51 comet nucleus 50 Kuiper Belt 50 Saturn moons 50 Pleiades 50 Solar System 50 pulsar 50 corona 50 cosmic microwave background 50 ringed planet 50 outer planets 50 exoplanet 50 ejecta 50 optical telescopes 50 moons 50 gravitationally 49 astrophysicists 49 interstellar medium 49 infrared wavelengths 48 Jupiter Saturn Uranus 48 heliosphere 48 sunspot 48 celestial objects 48 Enceladus 48 Gliese 47 gamma rays 47 single celled 47 Iapetus 47 ellipse 47 galactic 47 filaments 47 neutrinos 47 magnetosphere 47 orbits 47 Chandra X ray 47 comet 47 clusters 47 cosmologists 47 Sedna 47 suns