Asteroid belt
What is the asteroid belt?
A ring of leftover rock between Mars and Jupiter. It is not the wreckage of a planet. Jupiter’s gravity never let the rubble gather into one world. The dark gaps in it are resonances — the same tug, at the same point, over and over.
Rubble that never became a world
The belt’s total mass is about 3% of the Moon’s. Ceres, the largest body in it, is itself a dwarf planet. Switch the belt on in the solar system simulator and you are looking at leftover building material, not a destroyed planet.
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The gaps are Jupiter’s doing
An asteroid whose year is a simple fraction of Jupiter’s gets the same tug at the same point of its orbit, over and over, until it is pushed out. Those empty lanes are the Kirkwood gaps. The same gravity that kept the belt from becoming a planet is still editing it.