Related by context. Frequent words. (Click for all words.) 68 gravitational lensing 63 astronomical observations 62 astronomical objects 62 extrasolar planets 62 redshift 60 XMM Newton 60 astronomers 60 COROT 60 galaxy clusters 59 spectroscopic 59 astrophysicists 59 distant galaxies 59 astrophysical 59 gravitational wave 59 supernovae 59 optical telescopes 58 GRBs 58 globular cluster 58 quasars 58 globular clusters 58 gravitational waves 58 dynamical 58 elliptical galaxies 57 interferometry 57 galaxy cluster 57 magnetar 57 distant galaxy 56 Milky Way Galaxy 56 anisotropy 56 X ray emission 56 planets orbiting 56 dwarf galaxies 56 planets 56 ESO Very Large Telescope 56 extrasolar planet 56 infrared wavelengths 56 brown dwarfs 56 celestial objects 56 occultation 56 exoplanets 56 WM Keck Observatory 56 pulsars 56 neutron stars 56 Saturn rings 56 general relativity 55 quantum gravity 55 celestial bodies 55 NASA Chandra 55 theoretical physicists 55 Computer simulations 55 super Earths 55 anisotropic 55 telescopes 55 Spitzer Space Telescope 55 cosmologists 55 exoplanet 55 ejecta 55 cosmic microwave background 55 comet nucleus 55 supernovas 55 rocky planets 55 terrestrial planets 54 auroral 54 galaxies 54 Very Large Telescope 54 cosmological 54 Cassini Huygens 54 gamma ray bursts 54 gamma ray 54 Andromeda Galaxy 54 physicists 54 spacetime 54 Earth magnetosphere 54 outer planets 53 infrared telescope 53 quark gluon plasma 53 X ray Observatory 53 magnetosphere 53 Einstein theory 53 quasar 53 cosmic ray 53 Saturn moons 53 abundances 53 interstellar dust 53 X ray diffraction 53 Astronomers 53 dwarf galaxy 52 supernova explosions 52 supersymmetry 52 Gravity Probe B 52 substorms 52 adaptive optics 52 theoretical calculations 52 high temperature superconductivity 52 interferometer 52 Orion Nebula 52 laser pulses 52 photonic crystals 52 ecliptic 52 supernova remnant 52 CMEs