Related by context. Frequent words. (Click for all words.) 73 wavelengths 66 XMM Newton 65 infrared radiation 65 infrared 65 distant galaxies 64 redshift 61 quasars 61 extrasolar planets 61 spectroscopic 60 wavelength 60 distant galaxy 60 spectra 59 planets orbiting 58 Very Large Telescope 58 spatial resolution 58 exoplanets 58 gamma ray burst 58 heliosphere 57 gamma ray bursts 57 NASA Cassini spacecraft 57 orbits 57 galaxies 57 exoplanet 57 quasar 56 galaxy clusters 56 Spitzer Space Telescope 56 interstellar dust 56 gamma rays 56 cosmic microwave background 56 ultraviolet 55 rocky planets 55 globular clusters 55 laser pulses 55 dwarf galaxies 55 astronomers 55 nebula 55 infrared laser 55 ringed planet 55 Enceladus 55 magnetosphere 55 brown dwarf 54 Betelgeuse 54 luminosity 54 THEMIS 54 adaptive optics 54 Saturn rings 54 diffraction 54 polar regions 54 Milky Way galaxy 53 telescopes 53 celestial objects 53 brown dwarfs 53 nebulae 53 magnetic fields 53 mid latitudes 53 reflectance 52 spectroscopy 52 brightness 52 photons 52 interferometer 52 electromagnetic spectrum 52 spectrometer 52 planet orbiting 52 Cassini 52 latitudes 52 supernovae 52 X ray Observatory 52 gamma ray 52 interstellar medium 52 ionosphere 52 Raman spectroscopy 52 spectrometers 52 spectral 52 telescope 52 Space Telescope 52 spectrograph 52 ultraviolet light 52 planets 51 laser pulse 51 auroras 51 supermassive black hole 51 spiral galaxy 51 Planck 51 THz 51 Hubble Space Telescope 51 fluorescence 51 troposphere 51 WMAP 51 cosmic rays 50 supernova 50 JWST 50 northern latitudes 50 comet 50 galaxy 50 Cassini spacecraft 50 cosmic ray 50 gravitational waves 50 neutron stars 50 nanometers 50 HiRISE 50 Solar System