Related by context. Frequent words. (Click for all words.) 56 WIMPs 55 GeV 54 ionosphere 54 cosmic ray 53 Kuiper belt 52 sunspot activity 52 redshift 52 auroral 52 gravitational lensing 51 aerosol particles 51 magnetar 51 magnetosphere 51 lunar poles 51 perigee 51 spacetime 51 X ray emission 51 latitudes 51 cosmic rays 51 lithosphere 51 albedo 51 oxygen atom 51 HD #b [002] 51 picosecond 50 occultation 50 Uranus 50 super Earths 50 radioactive decay 50 Fomalhaut 50 infrared wavelengths 50 magnetic fields 50 polar regions 50 meteoroid 50 quantum mechanics 50 substorms 50 subatomic particle 50 troposphere 50 astronomical objects 49 fermions 49 thermosphere 49 planets 49 geomagnetic storms 49 habitable planets 49 GRBs 49 Eta Carinae 49 subduction zones 49 auroras 49 ionized gas 49 Enceladus 49 meteoroids 49 brown dwarfs 49 electron beams 49 anisotropy 49 angular momentum 49 planet orbits 49 sunspot cycle 49 constellation Perseus 49 astrophysical 49 excitons 49 relativistic 48 supermoon 48 supersymmetry 48 bandgap 48 cirrus clouds 48 polar caps 48 hydrogen atom 48 infrared radiation 48 extrasolar planet 48 Earth magnetosphere 48 constellation Leo 48 neutrons 48 cosmological constant 48 neutrino 48 neutrinos 48 Gliese #g 48 irradiance 48 ionospheric 48 galaxy cluster 48 cosmological 48 crustal 48 atomic nucleus 48 rocky planets 48 olivine 48 alpha particles 48 resonant frequency 47 planetary 47 muons 47 deuterium 47 gravitational waves 47 pineal gland 47 gamma ray bursts 47 radiative 47 Saturn moon Enceladus 47 exoplanets 47 atoms 47 ejecta 47 ozone depletion 47 electron spin 47 extrasolar planets 47 water vapor 47 silicates 47 cosmic microwave background