Related by context. Frequent words. (Click for all words.) 52 Cassiopeia 51 Arcturus 51 Pleiades 51 Betelgeuse 48 nebula 47 Pollux 47 Aldebaran 46 perigee 46 constellation 45 Big Dipper 44 unaided eye 43 Phobos 43 supernova 43 Milky Way Galaxy 43 Regulus 42 Uranus 42 Procyon 42 Milky Way 42 planet orbiting 42 infrared wavelengths 42 extrasolar planet 42 Sedna 41 meteors 41 fainter 41 Io 40 XMM Newton 40 bluish 40 circular orbit 40 spiral galaxy 40 gamma ray burst 39 Saturn rings 39 Saturn 39 galaxy 39 constellations 39 aurora 39 twinkles 39 galaxy cluster 39 equinox 39 distant galaxy 39 Nebula 39 crescent moon 39 luminosity 39 orbits 39 redshift 39 HD #b [002] 39 planets orbiting 38 nebulae 38 planets 38 suns 38 Perseids 38 Solar System 38 Planck 38 spiral galaxies 38 pulsar 38 Andromeda 37 extrasolar planets 37 sunspot 37 gamma ray bursts 37 ringed planet 37 neutron star 37 brown dwarf 37 Sagittarius 37 Cygnus 37 equator 37 Planets 36 orb 36 Charon 36 supernovae 36 ellipse 36 meteor shower 36 moons 36 Virgo 36 Eris 36 exoplanets 36 shines brightly 36 auroras 36 Perseid meteor shower 36 supernova explosion 36 elliptical galaxies 36 Vesta 35 quasar 35 distant galaxies 35 partial eclipse 35 globular clusters 35 celestial 35 Venus 35 meteor showers 35 celestial objects 35 rocky planets 35 Jupiter 35 Gliese 35 Antares 35 cometary 35 Aurora Borealis 35 elliptical orbit 35 heliosphere 35 comet 35 dwarf galaxies 35 magnetosphere 35 supermassive black hole 34 cosmic microwave background