Related by context. Frequent words. (Click for all words.) 55 crescent moon 54 constellation Orion 53 constellation Leo 52 occultation 51 constellation Perseus 51 Geminids 51 ringed planet 50 innermost planet 50 Leonid meteor shower 50 infrared wavelengths 50 moonrise 50 reddish hue 49 visible wavelengths 49 Perseid meteor shower 49 skywatchers 49 sky gazers 49 Comet McNaught 49 unaided eye 48 Opportunity rover 48 optical telescope 48 Milky Way Galaxy 48 HD #b [002] 48 supermoon 48 shorter wavelengths 48 X ray emission 48 umbra 48 Perseids 48 ecliptic 48 Crab Nebula 48 phosphorescence 48 Earth magnetosphere 48 partial lunar eclipse 48 sunrays 47 planet orbits 47 celestial object 47 moon Charon 47 solar eclipse 47 comet nucleus 47 X ray beam 47 auroras 47 autumnal equinox 46 Orion Nebula 46 crescent 46 Sensing Satellite LCROSS 46 rover Opportunity 46 blindingly bright 46 Cabeus crater 46 heliosheath 46 Saturn rings 46 LED headlamps 46 extrasolar planet 46 Pleiades 46 orange hue 45 sun 45 Mimas 45 sunbeam 45 Comet Tempel 1 45 supernova remnant 45 Eta Carinae 45 Voyager spacecraft 45 lunar eclipse 45 annular eclipse 45 Andromeda Galaxy 45 reddish orange 45 moon 45 planetary nebula 45 Jupiter Saturn 45 vernal equinox 45 equinox 45 equinoxes 45 Saturn moon Enceladus 45 Rover Opportunity 45 planetary nebulae 45 Leonids 44 New Horizons spacecraft 44 haloes 44 aurora 44 comet 44 interplanetary spacecraft 44 reddish purple 44 Kuiper belt 44 accretion disk 44 solar corona 44 Gliese #g 44 partial eclipse 44 star Gliese 44 microlensing 44 photometer 44 total lunar eclipse 44 LED illumination 44 XMM Newton 44 Martian equator 44 perigee 44 Aurora Borealis 43 optical telescopes 43 Cancri 43 distant galaxy 43 eyepiece 43 ellipse 43 brightness 43 celestial objects