Related by context. Frequent words. (Click for all words.) 82 brown dwarfs 71 exoplanet 69 rocky planets 68 exoplanets 67 planets orbiting 67 planet orbiting 67 quasar 67 supernova 66 galaxies 66 neutron star 66 extrasolar planets 66 distant galaxy 66 quasars 65 supernovae 65 gamma ray burst 64 supermassive black hole 63 Gliese 63 Milky Way galaxy 63 planets 63 pulsar 62 nebula 62 habitable zone 62 redshift 62 neutron stars 61 distant galaxies 61 Sedna 61 dwarf galaxies 60 galaxy 60 galaxy clusters 60 Milky Way 59 Spitzer Space Telescope 59 orbits 59 supermassive black holes 59 nebulae 58 gamma ray bursts 58 pulsars 57 Enceladus 57 positrons 57 astronomers 57 comets 57 Kuiper Belt 57 neutrino 56 Astronomers 56 deuterium 56 supernovas 55 neutrinos 55 infrared wavelengths 54 orbiting 54 UB# [003] 54 fainter 54 comet 54 Saturn rings 54 nuclei 53 asteroid belt 53 X ray Observatory 53 atoms 53 asteroids 53 gamma rays 52 sunspot 52 neutrons 52 hydrogen atoms 52 spectroscopic 51 GRB 51 astrophysicists 51 asteroid 51 Solar System 51 Pluto 51 SDSS 51 quark 50 corona 50 suns 50 Big Bang 50 Iapetus 50 gravitational waves 50 Cassiopeia 50 cosmic ray 50 organic molecules 49 cosmic microwave background 49 WMAP 49 infrared radiation 49 Harvard Smithsonian 49 cosmic rays 49 moons 49 elliptical orbit 49 dwarf planet 49 luminosity 49 astrophysical 49 Perseids 48 J# [002] 48 celestial objects 48 planetary 48 Astrophysical Journal Letters 48 Uranus 48 Astrophysical Journal 48 Galaxies 48 NASA Chandra 48 Very Large Telescope 48 photons 47 Saturn moon 47 subatomic particles 47 Kepler