Related by context. Frequent words. (Click for all words.) 73 supernovae 67 redshift 67 elliptical galaxies 67 supernovas 65 galaxy clusters 64 quasars 64 globular clusters 64 galaxies 64 brown dwarfs 64 quasar 63 spiral galaxies 63 gamma ray bursts 62 supermassive black holes 61 dwarf galaxies 61 pulsars 61 supernova 60 cosmological 60 spectroscopic 60 distant galaxies 60 gravitational lensing 60 rocky planets 60 spectra 59 neutron stars 59 cosmic microwave background 59 astrophysical 59 supernova explosion 59 XMM Newton 58 neutrinos 58 exoplanets 58 astrophysicists 58 extrasolar planets 58 cosmologists 58 astronomers 58 galaxy cluster 58 neutron star 58 gamma rays 58 nebulae 57 Milky Way Galaxy 57 terrestrial planets 57 planets orbiting 57 gamma ray burst 57 brown dwarf 56 exoplanet 56 gravitational waves 56 pulsar 56 neutrino 56 infrared wavelengths 56 distant galaxy 56 WMAP 56 supermassive black hole 55 deuterium 55 HD #b [002] 55 planets 55 cosmic rays 55 gamma ray 54 interstellar medium 54 dynamical 54 nuclei 54 magnetic fields 54 Milky Way 54 galaxy 54 antimatter 54 optical telescopes 53 luminosity 53 CMEs 53 positrons 53 extrasolar planet 53 Betelgeuse 53 celestial objects 53 spectroscopy 53 radioactive decay 53 Milky Way galaxy 53 NASA Chandra 53 X ray Observatory 53 nebula 52 high temperature superconductors 52 WM Keck Observatory 52 planet orbiting 52 filaments 52 photons 52 corona 52 subatomic particles 52 GRB 52 atomic nuclei 52 spacetime 52 Spitzer Space Telescope 52 cosmic ray 52 general relativity 52 wavelengths 52 comets 51 abundances 51 cosmology 51 amplitudes 51 binary 51 Saturn rings 50 subatomic 50 Raman spectroscopy 50 Astrophysical Journal 50 neutron 50 isotopic 50 wavelength