A scientific team from the Harvard-Smithsonian Center for Astrophysics proposes that a group of 700 or so unusual asteroids are excellent evidence for their hypothesis that the planet Jupiter’s orbit moved some 50 million miles closer to the sun as our planetary system was forming.

These asteroids, called the Hilda asteroids, orbit the sun in very elongated elliptical orbits three times each two Jupiterian years. Their computer simulations demonstrate that, if Jupiter had migrated that distance toward the sun in the course of 100,000 years, all Hilda objects that had circular orbits would have been propelled out of the solar system—leaving only those with elliptical orbits and the periodicity observed.
New Scientist

–From the September 2004 Austin Review KB