Related by context. Frequent words. (Click for all words.) 82 gamma ray bursts 73 supernova 70 supernovae 69 quasar 69 neutron star 67 pulsar 67 quasars 67 gamma rays 66 distant galaxies 66 galaxies 66 supermassive black hole 65 brown dwarf 64 pulsars 64 exoplanets 64 neutron stars 64 planet orbiting 63 exoplanet 63 comet 63 solar flares 62 supernovas 62 redshift 62 nebula 62 gravitational waves 62 galaxy 62 GRB 62 brown dwarfs 61 galaxy clusters 61 cosmic ray 61 Milky Way galaxy 61 astronomers 61 cosmic rays 60 extrasolar planets 60 neutrino 59 X ray Observatory 59 cosmic microwave background 59 neutrinos 59 planets orbiting 59 NASA Chandra 58 gamma ray 58 sunspot 58 auroras 58 supermassive black holes 58 comets 58 infrared wavelengths 58 Milky Way 57 Saturn rings 57 infrared radiation 57 dwarf galaxies 57 rocky planets 57 Astronomers 56 aurora 56 Spitzer Space Telescope 56 asteroid 56 astrophysicists 56 Space Telescope 55 fainter 55 asteroids 55 Sedna 55 laser pulse 55 Gliese 55 planets 55 Enceladus 55 WMAP 55 Iapetus 55 nebulae 54 corona 54 impactor 54 Solar System 54 laser pulses 53 meteor shower 53 orbits 53 Cassini 53 meteors 53 orbiting 53 telescope 52 Big Bang 52 spectroscopic 52 magnetosphere 52 Perseids 52 sunspots 52 meteor 51 photons 51 ionosphere 51 luminosity 51 celestial objects 51 magnetic fields 51 subatomic particles 51 wavelengths 51 LCROSS 50 spectrograph 50 Cassini spacecraft 50 meteor showers 50 moon Titan 50 neutrons 50 Higgs boson 50 Saturn moon 50 Tempel 1 50 Hubble Space Telescope 49 atomic particles 49 Cassiopeia 49 volcanism