Related by context. Frequent words. (Click for all words.) 59 crater 58 Victoria Crater 55 rock outcropping 54 volcanic crater 53 lava 52 caldera 50 glacier 50 rocky outcrop 50 comet nucleus 49 Itokawa 49 Martian surface 49 ringed planet 48 volcano crater 48 molten rock 48 extinct volcano 48 volcanic 47 seafloor 47 lava flows 47 volcano 47 lava flow 47 Saturn rings 47 boulder strewn 46 rocks 46 volcanic rock 46 Great Rift Valley 46 glacial lake 46 pyroclastic flows 46 butte 46 ridge 45 basalt 45 Kilauea volcano 45 dry riverbed 45 glacial lakes 45 craters 45 cliffs 45 rover Opportunity 44 canyon rim 44 volcanoes 44 canyon 44 volcanic activity 44 outcrop 44 magma 44 equatorial 44 orbiting spacecraft 44 waterfall 44 ejecta 44 comet 43 moon 43 volcanism 43 outcropping 43 coronal mass ejection 43 crevasses 43 treeline 43 martian 43 canyon walls 43 riverbed 43 massif 43 NASA Cassini spacecraft 43 sand dune 43 mountain slopes 43 lunar surface 42 Saturn moon 42 rocky terrain 42 plume 42 comet Tempel 1 42 sheer cliffs 42 NASA Mars Reconnaissance 42 outcroppings 42 equator 42 gullies 42 sedimentary rock 42 outcrops 42 dust devils 42 boulders 42 Pacific Ocean 42 molten lava 42 Iapetus 42 Mount Kilimanjaro 42 Meridiani Planum 42 jagged peaks 42 ridges 42 geologically active 41 Jupiter moons 41 volcanic islands 41 dune 41 sandstone cliffs 41 Gusev Crater 41 rover 41 petroglyph 41 infrared telescope 41 Cassini 41 X ray emission 41 Andes Mountains 41 glacial melt 41 moraine 41 plumes 41 asteroid 41 volcanos 41 active volcanoes 41 Comet Tempel 1 41 mountain