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asteroid belt – n. a gathering of any one of thousands of small planets that circle around the sun
dwarf planet – n. an object in space that looks like a small planet but lacks certain technical qualities that are required for it to be classed as such
geologically – adv. in a way that relates to rocks, land, or processes of land formation
reservoir – n. a place where a liquid is stored
regional – adj. a part of a country or world that is different or separate from other parts in some way
scale – n. the size or level of something especially in comparison to something else
global – adj. involving the entire world
crater – n. a large round hole in the ground made by the explosion of a bomb or by something falling from the sky
microbial – adj. an extremely small living thing that can only be seen with a microscope
quite – adv. to a very noticeable degree or extent
