Related by context. Frequent words. (Click for all words.) 78 galaxy clusters 76 galaxies 74 quasar 70 supermassive black hole 69 nebula 69 quasars 68 redshift 68 distant galaxies 67 gamma ray burst 67 neutron star 66 galaxy 66 Milky Way galaxy 66 Milky Way 66 pulsar 66 brown dwarf 65 exoplanet 64 supernova 64 exoplanets 63 supermassive black holes 63 supernovae 63 rocky planets 62 brown dwarfs 62 Saturn rings 61 planets orbiting 61 comet 61 Enceladus 60 planets 60 gamma ray bursts 60 neutron stars 60 Spitzer Space Telescope 60 extrasolar planets 60 astronomers 59 pulsars 59 cosmic microwave background 59 Sedna 59 Gliese 58 atoms 58 supernovas 58 Kuiper Belt 58 infrared wavelengths 58 corona 57 gravitational waves 57 sunspot 57 neutrino 56 nuclei 56 orbits 56 gamma rays 56 fainter 56 Astronomers 56 magnetosphere 56 nebulae 55 infrared radiation 55 GRB 55 luminosity 55 hydrogen atoms 55 asteroid belt 55 magnetic fields 55 spectroscopic 55 spectra 54 gamma ray 54 NASA Chandra 54 comets 54 neutrinos 53 photons 53 asteroids 53 Cassiopeia 53 asteroid 53 Solar System 53 cosmic rays 53 Cassini spacecraft 53 Saturn moon 53 galactic 53 gravitational 53 Uranus 53 moon Titan 52 Cassini 52 Space Telescope 52 astrophysicists 52 Very Large Telescope 52 Astrophysical Journal Letters 52 filaments 52 solar flares 51 subatomic particles 51 photon 51 vortices 51 proton 51 electron 51 dynamical 51 celestial objects 51 electrons 51 general relativity 51 protons 51 sunspots 50 NGC 50 particles 50 elliptical orbit 50 moons 50 starlight 50 Astrophysical Journal 50 planetary 50 celestial bodies