Asteroids Coming of Age

Richard P. Binzel

M.I.T.

January 1, 2001 marks not only the beginning of the new millennium, but also the beginning of the third century of asteroid studies. This talk will trace the growth of the field starting with William Herschel's assessment of these objects (and giving them their "asteroid" name). The talk will further explain the major milestones by Kirkwood and Hirayama, the discovery of Trojan asteroids, and the discovery and realization that some asteroid orbits cross that of the Earth. This talk will further address: How has the field grown in the 20th century and what factors have most contributed to that growth? What are the major findings about the nature of asteroids (compositions, structure, satellites)? What evidence leads us to the conclusion they are remnants of a planet that failed to form rather than the historical notion of a broken-up planet? What have we learned from our first spacecraft missions to asteroids? Where are asteroid studies headed in their third century?