Millions of asteroids orbit between Mars and Jupiter, but their total mass is just 4% of the Moon’s, too small to form a planet.
Early astronomers thought Ceres and others were fragments of a destroyed planet, later named Phaëthon.
The disruption theory claimed a planet was destroyed by Jupiter’s gravity or a collision.
Iron meteorites from the belt vary in composition, suggesting they came from different bodies, not one planet.
Scientists now believe no planet ever existed there; the belt likely holds leftover material from the solar system’s birth.
Jupiter’s gravity prevents the asteroids from combining, making future planet formation in the belt impossible