Related by context. Frequent words. (Click for all words.) 72 Milky Way 70 distant galaxy 69 Milky Way galaxy 68 spiral galaxy 67 Betelgeuse 66 distant galaxies 66 nebula 66 galaxies 65 galaxy 63 quasar 63 extrasolar planets 63 planets 63 planets orbiting 63 planet orbiting 62 Solar System 62 nebulae 62 supernovae 62 exoplanets 61 gamma ray burst 61 neutron star 61 brown dwarfs 61 rocky planets 60 brown dwarf 60 galaxy clusters 60 pulsar 60 supernova 60 quasars 60 neutron stars 60 Pleiades 59 gamma ray bursts 59 astronomers 59 supermassive black hole 59 dwarf galaxies 59 Andromeda 59 supernovas 59 galactic 58 exoplanet 58 celestial objects 58 fainter 58 Cassiopeia 58 Saturn rings 58 Galaxies 57 comet 57 redshift 57 Sedna 57 supermassive black holes 57 Perseids 56 Enceladus 56 orbiting 56 orbits 56 Spitzer Space Telescope 55 gravitational waves 55 comets 55 Gliese 55 pulsars 55 Astronomers 54 infrared wavelengths 54 Iapetus 54 celestial bodies 54 Kuiper Belt 53 moons 53 asteroid belt 53 gamma rays 53 meteors 52 Uranus 52 solar flares 52 Earths 52 asteroids 52 Space Telescope 52 cosmic microwave background 52 asteroid 51 constellations 51 Very Large Telescope 51 telescopes 51 celestial 51 Saturn moon 51 constellation 51 NASA Cassini spacecraft 51 meteor shower 51 Cassini 50 aurora 50 neutrinos 50 sunspot 50 NASA Chandra 50 corona 50 astrophysicists 50 Halley Comet 50 Black Holes 50 telescope 50 cosmic rays 50 moon Titan 50 positrons 49 cosmic ray 49 Planets 49 cosmic 49 neutrino 49 meteor 49 auroras 49 luminosity 49 Earth 49 Arcturus