Related by context. Frequent words. (Click for all words.) 74 XMM Newton 68 NASA Chandra 68 X ray Observatory 67 ESO Very Large Telescope 64 Galaxy Evolution 64 microlensing 63 Spitzer Space Telescope 63 Spectrometer 63 Very Large Telescope 62 WM Keck Observatory 62 X ray telescope 62 Space Telescope 62 optical telescopes 62 X ray emission 62 COROT 61 NASA ESA Hubble 61 NASA Cassini spacecraft 61 spectroscopic 61 astronomers 61 spacecraft orbiting 61 GRB # 60 infrared telescope 60 Keck Observatory 60 Hubble observations 59 NASA Cassini 59 STIS 59 solar corona 59 Cassini spacecraft 59 Cassini Huygens 59 distant galaxies 59 OSIRIS 59 interplanetary spacecraft 59 NASA Kepler 59 Kepler telescope 58 NASA Lunar Reconnaissance 58 active galactic nuclei 58 gravitational lensing 58 NICMOS 58 OGLE 58 SMOS 58 gamma ray burst 58 star Gliese 58 quasars 57 astronomical objects 57 comet nucleus 57 astronomical observations 57 NASA Aqua 57 Hinode 57 extrasolar planet 57 gravitational wave 57 Envisat 57 cosmic microwave background 56 interferometry 56 distant galaxy 56 Moderate Resolution 56 ESA Mars 56 spectrometer 56 Cancri 56 NASA Mars Reconnaissance 56 galaxy clusters 56 adaptive optics 56 Astrophysicists 56 galaxy cluster 56 quasar 56 Gemini Observatory 56 accretion disk 56 optical telescope 56 Chandra X ray 56 Cassini orbiter 56 MARSIS 55 Mars orbiter 55 Advanced Camera 55 infrared wavelengths 55 VLBA 55 exoplanet 55 planets orbiting 55 planetary nebulae 55 THEMIS 55 Mars Reconnaissance Orbiter 55 synchrotron radiation 55 NASA Mars Odyssey 55 Arecibo Observatory 55 planetary missions 55 ESRF 55 redshift 55 Very Large Array 55 beamline 55 optical microscopy 55 planets circling 55 supernova remnant 54 Voyager spacecraft 54 HD #b [002] 54 Garching Germany 54 magnetar 54 GRBs 54 spectrograph 54 spectrometers 54 orbiting telescope 54 CALIPSO 54 Saturn moon Enceladus 54 orbiting observatory