Related by context. Frequent words. (Click for all words.) 58 microlensing 57 infrared telescope 57 COROT 55 optical telescope 55 astronomer 55 X ray telescope 54 astronomers 54 Space Telescope 54 astrophysicists 54 interplanetary spacecraft 53 WM Keck Observatory 53 Titan Saturn 53 Cassini Huygens 53 SMOS 53 OGLE 53 Hubble observations 52 Keck Observatory 52 Galaxy Evolution 52 XMM Newton 52 extrasolar planets 52 planetary scientist 52 ESO Very Large Telescope 52 spectroscopic 52 optical telescopes 52 spacecraft orbiting 52 Astrophysicist 52 planetary missions 52 astronomical observations 51 astrophysical 51 Lick Observatory 51 JWST 51 astronomical observatory 51 Jet Propulsion Laboratory JPL 51 Arecibo Observatory 51 X ray Observatory 51 orbiting 51 spacecraft 51 Mars Pathfinder 50 Pan STARRS 50 OSIRIS 50 rovers Spirit 50 astrophysicist 50 CALIPSO 50 interferometer 50 spectrograph 50 CloudSat 50 NASA Kepler 50 PASADENA Calif. NASA 49 asteroid 49 THEMIS 49 interferometry 49 Gemini Observatory 49 Gamma ray bursts 49 GOCE 49 New Horizons spacecraft 49 Voyager spacecraft 49 telescope 49 orbiting spacecraft 49 orbit insertion 49 moon Charon 49 orbiting Mars 49 NASA ESA Hubble 49 Solar System 49 planetary exploration 49 Cancri 49 exoplanet 49 planetary nebulae 49 NASA Chandra 49 adaptive optics 48 Oceansat 2 48 extrasolar planet 48 Suzaku 48 NASA Cassini spacecraft 48 Spectrometer 48 ion propulsion 48 robotic spacecraft 48 supernova explosion 48 Astronomer 48 theoretical physicist 48 Earth Observing 48 theoretical physicists 48 NASA Lunar Reconnaissance 48 Spitzer Space Telescope 48 telescopes 48 magnetar 48 planetary science 48 Laboratory Pasadena 48 infrared spectrometer 47 numerical simulations 47 Astronomers 47 cosmologists 47 exoplanets 47 stargazer 47 Itokawa 47 Lunar Reconnaissance Orbiter 47 EPOXI 47 gravitational lensing 47 IceCube 47 Space Agency 47 astrophysics 47 planet orbiting