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dissolve – v. to turn from a solid into a liquid
meteorite – n. a piece of rock or metal that has fallen to the ground from outer space: a meteor that reaches the surface of the Earth without burning up entirely
quintillion – n. a number equal to 1 followed by 18 zeros
fossil – v. part of an animal or plant from thousands of year ago, preserved in rock
emerge – v. to appear from somewhere
source – n. something that provides what is wanted or needed
shallow – adj. not deep
impact – n. an act or event in which something strikes another thing
decade – n. a period of 10 years
