Related by context. Frequent words. (Click for all words.) 54 Andromeda Galaxy 52 dwarf galaxy 52 galaxy cluster 51 astronomers 50 galaxies 50 dwarf galaxies 49 XMM Newton 49 Saturn rings 49 galaxy clusters 48 distant galaxy 48 Orion Nebula 48 X ray emission 48 Milky Way 47 gravitational wave 47 extrasolar planet 47 COROT 47 optical telescopes 47 globular clusters 47 ejecta 47 extrasolar planets 47 quasar 47 Milky Way galaxy 46 spiral galaxies 46 Large Magellanic Cloud 46 heliosphere 46 Eta Carinae 45 nebula 45 Milky Way Galaxy 45 brown dwarfs 45 supernova remnant 45 amateur astronomers 45 supernova explosion 45 Geminids 45 elliptical galaxies 44 spiral galaxy 44 distant galaxies 44 magnetar 44 Saturn moons 44 skywatchers 44 super Earths 44 supernovae 44 Space Telescope 44 Betelgeuse 44 interstellar medium 44 rocky planets 43 occultation 43 meteoroids 43 Galaxies 43 Sedna 43 supernova explosions 43 HD #b [002] 43 Andromeda 43 sunspot 43 supernova 43 gravitational waves 43 redshift 43 NASA Chandra 43 globular cluster 43 pulsar 42 GRBs 42 pulsars 42 comet nucleus 42 accreting 42 aerosol particles 42 NASA Cassini spacecraft 42 neutrino 42 gamma ray burst 41 unaided eye 41 X ray Observatory 41 planet orbiting 41 observatories 41 Astronomers 41 Saturn moon 41 quasars 41 Cassini Huygens 41 neutron star 41 spacetime 41 ringed planet 40 astrophysicists 40 cometary 40 meteor 40 Pleiades 40 Jupiter moons 40 astronomical observations 40 Gliese 40 orbiting spacecraft 40 telescopes 40 exoplanet 40 WM Keck Observatory 40 gamma ray bursts 40 Solar System 40 star gazers 40 volcanic activity 40 nebulae 40 brown dwarf 40 supermassive black holes 40 ESO Very Large Telescope 40 WMAP 40 Cassini spacecraft 40 Very Large Telescope 40 dynamical