Related by context. Frequent words. (Click for all words.) 70 distant galaxies 70 celestial objects 67 quasars 64 nebulae 64 extrasolar planets 63 planets orbiting 63 distant galaxy 63 XMM Newton 62 planets 62 exoplanet 62 gamma ray bursts 62 exoplanets 62 supernovae 62 infrared wavelengths 62 galaxies 60 rocky planets 60 pulsars 59 brown dwarfs 59 astronomers 59 gamma ray burst 59 Milky Way galaxy 59 comet 59 astrophysical 59 interstellar dust 58 supernovas 58 spectroscopic 58 planet orbiting 57 comets 57 redshift 57 galaxy 57 quasar 56 gravitational waves 56 Spitzer Space Telescope 56 galaxy clusters 56 Saturn rings 56 supernova 56 auroras 56 Solar System 56 NASA Chandra 56 Enceladus 55 celestial bodies 55 nebula 55 spiral galaxy 55 neutron stars 55 dwarf galaxies 55 telescopes 55 wavelengths 55 astronomy 55 meteorites 54 spectra 54 brown dwarf 54 Milky Way 54 neutron star 54 cosmic rays 53 meteors 53 pulsar 53 Kuiper Belt 53 aurora 53 infrared radiation 53 X ray Observatory 53 solar flares 53 polar regions 52 telescope 52 orbits 52 Sedna 52 astrophysicists 52 Cassini 52 supermassive black holes 52 cosmic microwave background 52 HiRISE 52 Very Large Telescope 52 magnetosphere 52 supermassive black hole 52 Perseids 52 asteroids 52 gamma rays 51 NASA Cassini spacecraft 51 cosmologists 51 constellations 51 Betelgeuse 51 ringed planet 51 infrared 51 neutrino 51 neutrinos 51 interstellar medium 51 cosmic ray 51 THEMIS 51 SDSS 50 amateur astronomers 50 meteor showers 50 planetary science 50 magnetic fields 50 cosmos 50 heliosphere 50 JWST 50 Planck 50 WMAP 50 gamma ray 50 corona 50 Astronomy 50 Astronomers