Related by context. Frequent words. (Click for all words.) 74 VIRTIS 63 infrared mapping spectrometer 60 XMM Newton 59 spectrographs 59 ESO Very Large Telescope 58 Galileo spacecraft 58 NASA Aqua 58 NASA Spacecraft 58 NASA Cassini spacecraft 58 Resolution Stereo Camera 58 solar corona 58 ESA Mars 58 Adaptive Optics 57 photometer 57 NASA Cassini 57 ultraviolet wavelengths 57 Spectrometer 57 Mauna Kea Hawaii 57 Very Large Telescope 57 System THEMIS 57 X ray emission 57 spacecraft orbiting 56 MODIS 56 exosphere 56 HRSC 56 NASA ESA Hubble 56 Imaging Spectroradiometer MODIS 56 HD #b [002] 56 infrared spectrometer 56 HiRISE camera 56 Galaxy Evolution 56 Spitzer Space Telescope 56 unaided eye 56 Flyby 55 Very Large Array 55 Hubble observations 55 optical wavelengths 55 WFC3 55 Hubble Ultra 55 photosphere 55 COROT 55 interferometric 55 polar vortex 55 Mini SAR 55 noctilucent clouds 55 Moderate Resolution 55 Thermal Emission Imaging 54 NASA Chandra 54 Keck telescope 54 gravitational lens 54 NASA JPL Caltech 54 icy moons 54 active galactic nuclei 54 Tropical Rainfall Measuring 54 interferometry 54 photometry 54 radiometer 54 microscopic imager 54 microlensing 54 infrared radiation 53 star Gliese 53 photoluminescence 53 diffraction pattern 53 Valles Marineris 53 diffractive 53 LOFAR 53 Fluorescence 53 THEMIS 53 visible wavelengths 53 aurorae 53 multispectral imaging 53 moonlets 53 CRISM 53 STScI 53 Lunar Reconnaissance Orbiter LRO 53 NASA Mars Reconnaissance 53 NICMOS 53 WM Keck Observatory 53 Chandra X ray 53 optical telescopes 53 surface plasmons 53 LROC 53 Saturn moon Enceladus 52 Resolution Imaging 52 spectrometer 52 optical microscopy 52 Solar Dynamics 52 interplanetary spacecraft 52 Cassini orbiter 52 CALIPSO 52 alpha particle X ray 52 Mimas 52 particle detectors 52 supernova remnant 52 Meteorological Satellite 52 infrared wavelengths 52 Credit NASA JPL 52 National Optical Astronomy 52 cosmic microwave background 52 radar altimeter 52 moon Charon