This document discusses comets, asteroids, and meteors. It explains that comets are dirty snowballs that develop comas and tails as they near the sun due to melting ice. Comets originate from the Kuiper Belt outside Neptune and the distant Oort Cloud. Famous comets include Halley's Comet and Shoemaker Levy 9. Asteroids are large rocks that orbit between Mars and Jupiter, ranging in size from under 1 km to 300 km. Ceres, Pallas, and Vesta are famous asteroids. Meteors are small chunks of dust or rock from comets or asteroids that appear as streaks of light in the night sky, sometimes leaving meteorites if they reach the ground.