Related by context. Frequent words. (Click for all words.) 68 protoplanetary disk 66 silicates 65 solar nebula 64 olivine 63 lunar soil 63 aragonite 62 silicate 62 protostar 62 ionized gas 62 ultraviolet wavelengths 62 lithosphere 62 manganese oxide 62 planetary nebulae 62 ejecta 62 accretion disk 61 ionised 61 WASP #b 61 Gamma rays 61 Earthlike 61 shorter wavelengths 60 interstellar medium 60 elemental composition 60 osmium 60 carbonaceous 60 perovskite 60 planetesimals 60 micrometre 60 outer crust 60 SiO 2 60 X ray emission 60 Oort Cloud 60 isotope ratios 60 -# degrees Fahrenheit [002] 60 baryons 60 planetary nebula 60 carbonic acid 59 interstellar dust 59 alpha particles 59 ionize 59 visible wavelengths 59 radioactive decay 59 magnetar 59 apatite 59 iron oxides 59 aerosol particles 59 isotopic composition 59 SiO2 59 agglomerates 59 spacetime 58 electron density 58 galaxy NGC 58 WIMPs 58 nitrogen atoms 58 isotropic 58 Ultraviolet light 58 optical wavelengths 58 MgO 58 dye molecules 58 planet orbits 58 solar corona 58 clasts 58 cirrus 58 rocky planets 57 semisolid 57 silicon atoms 57 polar vortex 57 torus 57 spinel 57 magnetars 57 orbitals 57 mesosphere 57 copper oxides 57 active galactic nuclei 57 water vapor 57 supernova remnants 57 meteoroids 57 gravitationally 57 lavas 57 observable universe 57 spherules 57 kelvin 57 spiral galaxies 57 Ultraviolet radiation 57 antiprotons 57 nuclei 57 icy crust 57 kerogen 56 fluorescing 56 quanta 56 spectroscopic 56 tropospheric 56 monazite 56 Cosmic rays 56 Kuiper belt 56 spectrographs 56 HD #b [002] 56 Carina Nebula 56 GPa 56 heliosheath 56 neutron star 56 galaxy formation