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                                A rock that goes around the sun is = (asteroid, comet, meteor).  An object that crosses paths with Earth and enters the Earth's atmosphere = (asteroid, comet, meteor).  A mixture of frozen gases, ice, dust, and rock that moves in an irregular circle around the sun is = (asteroid, comet, meteor). 
                                A rock that goes around the sun is = asteroid.  An object that crosses paths with Earth and enters the Earth's atmosphere = meteor.  A mixture of frozen gases, ice, dust, and rock that moves in an irregular circle around the sun is = comet.