Related by context. Frequent words. (Click for all words.) 75 astrophysicists 74 Astronomers 71 Physicists 69 astronomers 69 cosmologists 67 physicists 62 Scientists 58 astronomer 58 astrophysicist 58 gravitational waves 58 distant galaxies 58 extrasolar planets 57 scientists 57 quasars 56 gamma ray bursts 56 galaxies 56 galaxy clusters 56 planetary scientist 56 Astrophysics 56 theoretical physicist 55 NASA Chandra 55 planets 55 brown dwarfs 55 cosmological 55 particle physics 55 nebulae 55 exoplanets 54 planets orbiting 54 supernovae 54 Astronomer 54 cosmology 53 gamma ray burst 53 Neuroscientists 53 SCIENTISTS 53 Einstein theory 53 astrophysics 53 rocky planets 53 Cosmology 53 Saturn rings 53 atomic particles 53 astronomy 53 Mathematicians 53 Boffins 53 physicist 52 physics 52 neutron stars 52 supernovas 52 Physicist 52 quasar 52 Astrophysical Journal 52 Space Telescope 52 supermassive black holes 52 neutrinos 51 Astronomy 51 subatomic particles 51 neutrino 51 redshift 51 cosmic microwave background 51 general relativity 51 Milky Way 51 celestial bodies 51 Astrobiology 51 Spitzer Space Telescope 51 Researchers 51 Very Large Telescope 51 galaxy 51 pulsars 51 comet 50 gamma rays 50 quantum mechanics 50 Astrophysical Journal Letters 50 Milky Way galaxy 50 neutron star 50 supernova 50 cosmic rays 50 spectroscopy 50 comets 50 infrared wavelengths 50 quantum physics 49 Dark Matter 49 pulsar 49 spectroscopic 49 magnetic fields 49 Solar System 49 exoplanet 49 geophysicists 49 cosmos 49 telescopes 49 subatomic 49 Geologists 49 asteroids 49 Physics 49 asteroid 49 astrobiology 48 nebula 48 telescope 48 Higgs boson 48 planetary 48 Big Bang theory 48 gamma ray 48 Telescope