Mass-depletion of the Asteroid Belt Estimated by Recent Chronology-Models Derived from Impact-Crater Investigations

The bombardment of the solar system by small bodies is well documented by image-investigations of cratering records on the surfaces of planetary bodies since the early 1960’s. The well investigated cratering record of Earth’s moon reveals a typical size-frequency distribution (SFD) leading to the well known lunar impact-chronology model. Comparisons of size-frequency distributions of the cratering-record on surfaces of planetary bodies of the inner solar system with the observed Near-Earth-Asteroid (NEA) population of the the asteroid belt has led to the conclusion that the asteroid belt acts as the major contributor to the impactor population for the planetary bodies of the inner solar system. This is, however, still in discussion for the outer solar system.