The Asteroid Belt is a belt of asteroids lying between the orbits of Mars and Jupiter in the Solar System.
The Asteroid Belt appears in the episode "Battle of the Planets" toward the end of the climactic battle, when Zim attempts to evade Dib by piloting Mars into the Belt. This ultimately proves to be an unwise and near-suicidal decision, as Mars nearly gets pulverized by the asteroids, and Zim is forced to take off in his Voot Cruiser.