Related by context. Frequent words. (Click for all words.) 61 nebulas 57 astronomical objects 57 Amateur astronomers 56 extrasolar 56 constellations 55 solar corona 55 Jupiter Saturn 55 celestial objects 54 Jupiter moons 54 Epsilon Eridani 53 Earthlike planets 53 planetary nebulae 53 gaseous planets 53 extraterrestrial civilizations 53 nebulae 52 GALEX 52 photosphere 51 planetary atmospheres 51 unaided eye 51 Exoplanet 51 planets orbiting stars 51 lunar craters 51 habitable planets 51 photometry 51 Andromeda galaxy 51 aurorae 50 Earthlike 50 constellation Taurus 50 active galactic nuclei 50 Eagle Nebula 50 Orion Nebula 50 celestial 50 stargaze 50 constellation Orion 50 interplanetary spacecraft 50 planets 50 transiting planets 50 potentially habitable 50 Meteor showers 50 innermost planet 49 Gamma ray bursts 49 Canis Major 49 infrared telescopes 49 X ray telescopes 49 Kepler #b 49 astronomical phenomena 49 Diviner 49 Galaxy Evolution 49 radial velocity 49 polar craters 49 icy moons 48 gravitationally bound 48 astrophysical 48 galaxy 48 Solar flares 48 Meteor Shower 48 VIRTIS 48 celestial bodies 48 exosphere 48 planet Uranus 48 XMM Newton 48 supernovas 48 elliptical orbits 48 planets circling 48 Kepler spacecraft 48 starbursts 47 laser altimeter 47 Andromeda Galaxy 47 distant galaxy 47 AGNs 47 Saturn moons 47 AKARI 47 Lunar eclipse 47 Magellanic Clouds 47 Comet McNaught 47 magnetars 47 planets orbiting 47 distant galaxies 47 Oort Cloud 47 SIRTF 47 Martian rocks 47 galaxy formation 47 Cepheids 47 galactic 47 extrasolar planets 47 horoscopes section 47 orbiting Hubble Space Telescope 47 earthquakes volcanoes 47 outer planets 47 infrared 46 celestial navigation 46 meteor showers 46 X ray emission 46 protostars 46 SkyScout 46 Stargazing 46 protoplanetary disks 46 optical wavelengths 46 Olympus Mons 46 orbiting planets 46 gravitational lens