Related by context. Frequent words. (Click for all words.) 63 redshifts 61 Cepheids 61 redshift 59 keV 59 geoid 59 radial velocity 58 solar corona 58 z = 58 elemental composition 58 active galactic nuclei 58 Type Ia supernovae 58 visible wavelengths 57 magnetars 57 optical wavelengths 57 X ray emission 57 solar irradiance 57 observable universe 57 WASP #b 57 photometry 57 cosmic microwave background 56 astronomical objects 56 diffraction pattern 56 galaxy cluster 56 Keck telescope 56 anisotropy 56 Cosmologists 56 planetary nebulae 56 radiative forcing 56 solar nebula 55 ultraviolet wavelengths 55 tropospheric 55 XMM Newton 55 gravitational lens 55 photometer 55 comet nucleus 55 infrared wavelengths 55 exosphere 55 microlensing 55 magnetar 55 baryons 55 cm -1 54 shorter wavelengths 54 supernova remnant 54 spectral signatures 54 star Gliese 54 interferometry 54 spectrographs 54 micrometre 54 gravitational wave 54 aerosol particles 54 Galaxy Evolution 54 planet orbits 54 Hubble observations 54 GeV 54 electron density 54 distant galaxies 53 WFC3 53 GRBs 53 galaxy clusters 53 Gamma ray bursts 53 substorm 53 celestial object 53 interferometric 53 quasars 53 Milky Way Galaxy 53 HD #b [002] 53 photometric 53 photoluminescence 53 optical telescopes 53 laser pulses 53 distant galaxy 53 sunspot numbers 53 moonlets 53 VIRTIS 52 irradiance 52 galaxy formation 52 spectroscopic 52 isotopic composition 52 muon 52 cosmic ray 52 frequency comb 52 negative refraction 52 auroral 52 Andromeda galaxy 52 gravitational lensing 52 amplitudes 52 supernova remnants 52 noctilucent clouds 52 microwave radiation 52 unobservable 52 isotope ratios 52 perihelion 51 interferometers 51 radiative 51 spherules 51 planet Uranus 51 oxygen isotopes 51 reflectance 51 Crab Nebula 51 unaided eye 51 attosecond