Related by context. Frequent words. (Click for all words.) 76 planets 74 planets orbiting 73 brown dwarfs 71 dwarf galaxies 71 extrasolar planets 70 exoplanets 70 habitable zone 69 brown dwarf 69 galaxies 68 exoplanet 68 planet orbiting 67 Milky Way galaxy 67 galaxy clusters 66 supernovae 66 neutron stars 65 quasars 65 comets 65 organic molecules 64 distant galaxies 63 Kuiper Belt 63 asteroids 63 supermassive black holes 62 Enceladus 61 Milky Way 61 quasar 61 supernovas 61 neutron star 61 nebulae 60 Solar System 60 supernova 60 supermassive black hole 59 galaxy 58 Spitzer Space Telescope 58 asteroid 58 Gliese 58 pulsars 58 comet 57 Astronomers 57 gravitational waves 57 meteorites 57 moons 57 gamma ray bursts 57 nebula 57 Saturn rings 57 redshift 57 gamma ray burst 57 astronomers 57 Saturn moon 57 Earths 56 Sedna 56 neutrino 56 celestial bodies 55 infrared wavelengths 55 asteroid belt 55 hydrothermal vents 55 atoms 55 magnetosphere 55 pulsar 55 orbits 54 hydrogen atoms 54 hematite 54 atomic particles 54 buckyballs 54 cosmic microwave background 54 nuclei 53 organic compounds 53 subatomic particles 53 planetary 53 neutrinos 53 moon Titan 53 Martian surface 53 Higgs boson 53 Meridiani Planum 53 deuterium 53 spectroscopic 53 cosmologists 52 antimatter 52 Iapetus 52 Galaxies 51 UB# [003] 51 astrophysicists 51 Martian soil 51 celestial objects 51 Astrophysical Journal Letters 51 fainter 51 molecules 51 craters 51 solar flares 50 NASA Chandra 50 sunspots 50 orbiting 50 polycyclic aromatic hydrocarbons 50 nanocrystals 50 interstellar space 50 hydrothermal 50 magnetic fields 50 volcanism 50 neutrons 50 gamma rays 50 Astrophysical Journal 50 Martian atmosphere