Related by context. Frequent words. (Click for all words.) 41 planet 40 arctic tundra 39 Camels 39 Earthlike 38 consume 38 super Earths 38 inhabit 37 arid regions 37 volcanic vents 36 omnivores 35 biodiverse 35 freshwater ecosystems 35 nonrenewable resources 35 Polar Regions 35 equatorial regions 35 hydrothermal vent 34 Gamma rays 34 planetary nebulae 34 guzzle 34 harshest environments 34 earths 34 oceans 34 habitable planets 34 desalinate 34 polar regions 34 creatures 33 photosynthesize 33 Kuiper Belt objects 33 lightest 33 hot Jupiters 33 volcanically active 33 driest continent 33 habitable planet 33 ecological footprints 33 rapidly depleting 33 marine reptiles 33 extrasolar planets 33 icecaps 33 freshwater 33 healthiest foods 33 atmospheric methane 33 lifeforms 33 asteroid Ceres 33 sequester carbon dioxide 33 Titan Saturn 32 fossil fuel 32 magnetars 32 inhabited 32 intelligent beings 32 prehistoric 32 emit 32 excrete 32 interplanetary spacecraft 32 moonlets 32 arid 32 pulverise 32 caloric sweeteners 32 majestic creatures 31 Gamma ray bursts 31 Earth 31 scarcest 31 Kuiper belt 31 Spitzer Space Telescope 31 semi arid 31 outgun 31 planets 31 earth 31 humans 31 Kuiper Belt 31 moon Charon 31 equator 31 orbiting 31 active galactic nuclei 31 habitable zones 31 Milky Way Galaxy 31 outmuscle 31 colonize 31 Mars 30 brown dwarfs 30 Cosmic rays 30 Cabeus crater 30 inhospitable 30 absorb carbon dioxide 30 Cancri 30 withstand 30 ultra lightweight 30 Earths 30 crushable 30 exoplanets 30 Camel 30 artificially sweetened 30 Orion Nebula 30 overpopulate 30 manmade 30 mightiest 30 planets orbiting 30 Replenishing 29 astrobiologists 29 rapidly urbanizing 29 camels 29 Milky Way