Related by context. Frequent words. (Click for all words.) 62 WASP #b 61 planetary nebulae 60 habitable zones 58 rocky planets 58 Oort Cloud 58 Gliese #g 57 star Gliese 57 Cepheids 56 HD #b [002] 56 radial velocity 56 Kuiper belt 56 solar nebula 56 Milky Way Galaxy 56 -# degrees Fahrenheit [002] 56 planet orbits 55 active galactic nuclei 55 radioactive decay 55 Lake Vostok 55 terrestrial planets 55 observable universe 55 super Earths 55 solar corona 55 planetesimals 55 COROT 55 ejecta 55 planetary nebula 54 polar vortex 54 supernova explosion 54 habitable planets 54 -# degrees Celsius [001] 54 magnetars 54 Orion Nebula 54 heliosheath 54 geologically active 54 comet nucleus 54 lunar poles 54 volcanic vents 54 brown dwarfs 54 Cancri 53 magnetar 53 galaxy cluster 53 Crab Nebula 53 Gamma rays 53 Meridiani 53 Voyager spacecraft 53 torus 53 dwarf galaxy 53 quark gluon plasma 53 interstellar medium 52 GeV 52 lunar soil 52 extrasolar planet 52 continental crust 52 celestial bodies 52 brown dwarf 52 Type Ia supernovae 52 habitable zone 52 Enceladus 52 planets 52 regolith 52 moon Europa 52 mud volcanoes 52 accretion disk 52 -# ° C [001] 52 nanosized 51 Milky Way galaxy 51 oceanic crust 51 galaxy clusters 51 subatomic particle 51 lithosphere 51 orbits 51 Large Magellanic Cloud 51 innermost planet 51 Gliese 51 Solar System 51 Iapetus 51 visible wavelengths 51 quasar 51 habitable planet 51 isotopic composition 51 planetoid 51 volcanically active 51 Martian equator 51 X ray emission 51 meteoroids 51 celestial object 51 hot Jupiters 51 planets orbiting 51 Cabeus crater 51 heliosphere 50 astronomical objects 50 methane hydrate 50 Saturn moon 50 supernova remnants 50 equatorial regions 50 millionths 50 exoplanet 50 Saturn moon Enceladus 50 morphologies 50 interstellar space 50 lava tubes