Related by context. Frequent words. (Click for all words.) 63 GRB # 60 X ray emission 59 XMM Newton 59 Gamma ray bursts 57 magnetar 57 gamma ray burst 56 Type Ia supernovae 56 GRBs 55 supernova remnant 55 gamma ray bursts 55 solar corona 55 quasar 54 Crab Nebula 54 photometric 54 Galaxy Evolution 54 quasars 54 astronomers 53 astronomical objects 53 infrared wavelengths 53 galaxy cluster 53 Gliese #g 53 HD #b [002] 52 microlensing 52 dwarf galaxy 52 planet orbiting 52 auroral 52 Hubble observations 52 exoplanet 52 celestial object 52 planetary nebulae 52 star Gliese 52 VLBA 52 planets circling 51 comet nucleus 51 brown dwarfs 51 OGLE 51 luminosity 51 Orion Nebula 51 extrasolar planet 51 spectra 51 accretion disk 51 supernova remnants 51 gravitational wave 51 X ray telescope 51 Eta Carinae 51 redshift 51 magnetic reconnection 50 gamma rays 50 distant galaxy 50 Andromeda galaxy 50 pulsars 50 cosmic ray 50 globular cluster 50 colliding galaxies 50 haloes 50 nebulae 50 COROT 50 brown dwarf 50 visible wavelengths 50 planet orbits 50 constellation Orion 50 Comet McNaught 49 Milky Way Galaxy 49 reflectance 49 optical telescopes 49 unaided eye 49 planetary nebula 49 gamma ray 49 spacecraft orbiting 49 supernova 49 cosmic microwave background 49 moon Charon 49 galaxy clusters 49 Betelgeuse 49 constellation Leo 49 interferometry 49 celestial objects 49 Fomalhaut 48 Andromeda Galaxy 48 elliptical galaxies 48 meteoroids 48 NASA Chandra 48 Large Magellanic Cloud 48 THEMIS 48 neutrino 48 planets orbiting 48 interplanetary spacecraft 48 X ray Observatory 48 GRB 48 ringed planet 48 brightness 48 pulsar 48 distant galaxies 48 NICMOS 48 gravitational waves 47 Earth magnetosphere 47 STIS 47 Leonids 47 X ray beams 47 Astronomers 47 extrasolar planets