Related by context. Frequent words. (Click for all words.) 64 optical telescope 62 astronomical observatory 61 ESO Very Large Telescope 61 telescope 61 infrared telescope 60 telescopes 60 astronomical observations 60 adaptive optics 59 Southern Observatory ESO 59 interplanetary spacecraft 58 XMM Newton 58 Cassini Huygens 57 WM Keck Observatory 57 IceCube 57 particle detector 57 optical telescopes 56 interferometer 56 NASA ESA Hubble 56 WFC3 56 optical microscope 56 GOCE 56 COROT 55 Very Large Telescope 55 VLBI 55 extrasolar planet 55 photometer 54 orbiting telescope 54 parabolic trough 54 OSIRIS 54 X ray telescope 54 Remote sensing 54 radial velocity 54 Spectrometer 54 orbiting observatory 54 microlensing 54 optical microscopy 54 spectroscopic 54 Pan STARRS 54 observatories 53 STIS 53 LCLS 53 Keck Observatory 53 radar altimeter 53 SMOS 53 Mauna Kea Hawaii 53 DubaiSat 1 53 Gravity Probe B 53 Spitzer Space Telescope 53 Nicolaus Copernicus 53 interferometry 53 IKONOS 53 Webb Telescope 53 spacecraft orbiting 53 polar orbiting 53 solar corona 53 MARSIS 53 photometry 53 remote sensing satellites 52 SELENE 52 synchrotron radiation 52 VLBA 52 astronomers 52 orbiting Saturn 52 NASA Cassini spacecraft 52 gravitational wave 52 Hubble observations 52 Thirty Meter Telescope 52 frequency comb 52 observatory 52 Envisat 52 CCD camera 52 hyperspectral 52 Mini SAR 52 ESA Mars 51 spectrometers 51 photoelectric effect 51 celestial object 51 CubeSat 51 ringed planet 51 robotic spacecraft 51 orbiting spacecraft 51 scanning electron microscope 51 optical microscopes 51 lunar orbiter 51 occultation 51 multispectral 51 geodesy 51 remote sensing satellite 51 Gravity Recovery 51 CALIPSO 51 CRISM 51 moon Charon 51 Space Agency 51 solar concentrator 51 Arecibo Observatory 51 HRSC 50 attosecond 50 Very Large Array 50 Galileo Galilei 50 Ariane rocket 50 JWST