We have collected a lot of new data in the seven years since the big blue books came out (Asteroids II, 1989, and Meteorites and the Early Solar System, 1988). Here we review how all this new data has changed our perceptions of the geology of the asteroid belt. The only way to a complete understanding of asteroid belt geology is through knowledge of the nature of the mysterious and elusive heating mechanism that differentiated the asteroids. If we can figure out what it was, then we will know something fundamental about the forces at work during the formation time of the Solar System. Some of the principal observations we can make to put constraints on the possibilities come from observations of main asteroid belt geology. The most pressing problem in the geology of the asteroid belt is in the inner belt. S-type asteroids are key to the inner main belt, but their meteorite linkage is ambiguous. Why do we care? Because--if the S-types are chondritic, then almost the entire main belt is primitive material, representing very early solar system time, but telling us almost nothing about the mysterious heating mechanism. If the S-types are differentiated, then the heating mechanism ceased functioning in the middle of the main belt at the 'dividing line' between primitive and differentiated material. This dividing line is the silicate rock melting temperature position in space of the mysterious heating event. The Bell Big Picture model of asteroid belt geology synthesized all the information available and established the position of this dividing line back in 1988. But there is now new data to consider.
Lunar and Planetary Science Conference
- Pub Date:
- March 1996
- ASTEROIDS: S-TYPE;
- SOLAR SYSTEM: EARLY