Related by context. Frequent words. (Click for all words.) 68 aurora 67 auroras 63 convective 62 ionosphere 62 sunspot 61 cosmic ray 61 gamma ray burst 61 geomagnetic 60 quasar 60 supernovae 59 gamma ray bursts 58 GRBs 58 XMM Newton 58 gravitational lensing 58 solar flares 58 magnetic fields 58 occultation 57 magnetosphere 57 sunspots 57 astrophysical 57 gravitational waves 57 galaxy cluster 57 dynamical 57 amplitudes 56 aurora borealis 56 CMEs 56 volcanism 56 oscillations 56 ejecta 56 Orion Nebula 55 quasars 55 distant galaxies 55 mid latitudes 55 nebula 55 spiral galaxies 55 gamma rays 55 sunspot activity 55 vortices 55 infrared wavelengths 54 Saturn rings 54 cosmic microwave background 54 superfluid 54 galaxies 54 Enceladus 54 supernova 54 interferometry 54 infrared radiation 54 NASA Cassini spacecraft 54 GRB 54 Eta Carinae 54 nuclei 54 cosmic rays 54 neutron star 54 THEMIS 53 redshift 53 pulsars 53 elliptical galaxies 53 spacetime 53 interstellar dust 53 celestial objects 53 gamma ray 53 spectra 53 nebulae 53 laser pulses 53 supernova explosion 53 geomagnetic storm 53 interstellar medium 53 geomagnetic field 53 galaxy clusters 52 extrasolar planets 52 astronomers 52 supernovas 52 starlight 52 pulsar 52 magnetic 52 atmospheric circulation 52 Iapetus 52 magmatic 52 unaided eye 52 corona 52 globular clusters 52 WMAP 52 neutron stars 52 supermassive black hole 52 neutrino 52 wavelengths 51 magnetization 51 equatorial 51 polar 51 crustal 51 filaments 51 convection 51 HD #b [002] 51 distant galaxy 51 cometary 51 ringed planet 50 planets orbiting 50 volcanic activity 50 perturbation 50 heliosphere 50 troposphere