Kirkwood Gaps
Related Category: Astronomy: General
regions in the
asteroid belt within which few asteroids are found. Astronomer Daniel Kirkwood first observed (1886) that few asteroids had an orbital period close to
1/2,
1/3, or
2/5 that of Jupiter. The gaps could have been formed by collisions between asteroids; however, the most widely accepted theory is that the gaps were formed by gravitational interactions with Jupiter, which over time would move any small body into another orbit.