Related by context. Frequent words. (Click for all words.) 61 XMM Newton 61 WMAP 60 infrared wavelengths 58 astronomical objects 58 distant galaxies 58 redshift 58 spectroscopic 57 distant galaxy 56 supernova remnant 56 NASA Cassini spacecraft 55 THEMIS 55 NASA Chandra 55 Mimas 55 SDSS 55 galaxy cluster 54 Gemini Observatory 54 Andromeda galaxy 54 X ray emission 54 astronomers 54 cosmic microwave background 54 comet nucleus 53 WM Keck Observatory 53 Orion Nebula 53 quasar 53 galaxy formation 52 hyperspectral 52 quasars 52 galaxy clusters 52 Saturn rings 52 interferometry 52 extrasolar planet 52 ESO Very Large Telescope 52 astrophysical 52 Spitzer Space Telescope 52 gravitational lensing 52 ringed planet 51 HiRISE 51 GRBs 51 IceCube 51 photometric 51 HD #b [002] 51 infrared telescope 51 Milky Way Galaxy 51 Space Telescope 51 celestial object 51 extrasolar planets 51 MODIS 51 galaxies 51 Arecibo Observatory 51 Cassini Huygens 51 Astrophysical Journal Letters 50 exoplanets 50 Very Large Array 50 heliosphere 50 Astrophysical Journal 50 Very Large Telescope 50 HRSC 50 auroral 50 optical microscopy 50 NASA Goddard 50 COROT 50 MESSENGER 50 GeV 50 cosmic ray 50 Cassini 50 celestial objects 50 JWST 50 Milky Way galaxy 49 Lick Observatory 49 adaptive optics 49 supernovae 49 Computer simulations 49 globular clusters 49 optical telescopes 49 Earth magnetosphere 49 Kepler telescope 49 infrared 49 exoplanet 49 multispectral 49 astronomical observations 49 Lowell Observatory 49 elliptical galaxies 49 Crab Nebula 49 X ray Observatory 49 gravitational wave 49 NASA Lunar Reconnaissance 49 MARSIS 49 scanning electron microscope 49 gamma ray burst 49 interferometer 49 scarps 48 Jupiter moons 48 gamma ray 48 Solar System 48 Astrophysicist 48 infrared spectrometer 48 unaided eye 48 Planck 48 Planetary Science 48 planets orbiting 48 Palomar Observatory