Related by context. Frequent words. (Click for all words.) 65 terrestrial planets 64 habitable planets 64 extrasolar planets 63 astronomical objects 63 planets 63 galaxy formation 61 brown dwarfs 61 rocky planets 60 planets orbiting 60 astronomers 60 GRBs 60 supernovae 60 COROT 60 gravitational lensing 59 XMM Newton 59 exoplanet 59 astrophysical 58 exoplanets 58 astrobiologists 58 nebulae 58 extrasolar planet 58 globular cluster 58 X ray emission 58 Milky Way Galaxy 58 gravitational wave 57 gamma ray bursts 57 quasars 57 galaxies 57 magnetar 57 celestial objects 57 neutrino 57 outer planets 57 globular clusters 57 distant galaxies 57 distant galaxy 57 brown dwarf 57 Jupiter moons 57 spectroscopic 57 super Earths 56 optical telescopes 56 comets 56 galaxy clusters 56 substorms 56 dwarf galaxies 56 OGLE 56 interferometry 56 pulsars 56 WIMPs 56 moon Charon 56 neutrinos 56 auroral 56 gravitational waves 56 planet orbiting 56 Andromeda Galaxy 55 Milky Way galaxy 55 planetary scientist 55 cosmic microwave background 55 hot Jupiters 55 redshift 55 magnetosphere 55 Gliese #g 55 Enceladus 55 elliptical galaxies 55 spacetime 55 geomagnetic 55 meteoroids 55 supernovas 55 Orion Nebula 54 planetary 54 astronomical observations 54 Kuiper belt 54 astrophysicists 54 celestial object 54 Earth magnetosphere 54 habitable planet 54 HD #b [002] 54 Andromeda galaxy 54 Spitzer Space Telescope 54 gamma ray burst 54 Jupiter Saturn 54 morphologies 54 comet nucleus 53 quasar 53 infrared wavelengths 53 supernova remnant 53 celestial bodies 53 Solar System 53 Saturn moons 53 martian 53 moon Europa 53 Saturn rings 53 THEMIS 53 ionospheric 53 supernova explosions 53 occultation 53 supernova explosion 53 cosmologists 53 interstellar dust 53 asteroids 53 neutron star 53 spectra