THIRTY YEARS OF ASTEROID SCIENCE: AN EMBARRASSMENT OF RICHES

The last thirty years have seen an explosion in our understanding of the asteroids, both within and outside the main belt between Mars and Jupiter. At the time of the founding of PGD in May 1981 roughly 2400 asteroids had well-established orbits, compared to over 280,000 today. Furthermore, not a single asteroid had been visited by spacecraft, greatly hampering progress. Since then, several asteroid flybys have occurred, Eros, Itokawa, and Vesta have been the targets of spacecraft rendezvous, and samples have been returned from Itokawa (with sample return also in NASA's future plans). Data from these missions, as well as Hubble Space Telescope data and radar experiments from Arecibo and Goldstone, have revolutionized asteroid geology and geophysics, showing asteroids to be a varied bunch with ongoing physical processes. I will discuss the past thirty years of progress in asteroid science, focusing on geological and geophysical aspects.