The origin of the asteroid main belt: Synthesis of mutually exclusive paradigms

Abstract

Abstract An origin of the asteroid main belt (MB) is usually considered in the framework of either (1) Olbers hypothesis on breaking of a small planet Phaethon, or (2) a hypothesis on a planet which failed to be accumulated in the protoplanetary cloud due to the Jovian perturbations with subsequent collisional evolution of its embryos. Both hypotheses have their own shortcomings. The possibility of explosion of the ice electrolysis products dissolved in icy envelopes of distant planets, which was suggested recently, apparently poses the Olbers hypothesis on a firm basis and explains a variety of the asteroid MB features especially if one takes into account a success of this approach in explaining and predicting properties of other minor body groups. However, gasdynamic calculations revealed that a non-central explosion of the envelope of a M = 0.2Mmoon planet produces numerous not very big (up to ∼ 50 km) icy fragments - the future C-asteroids, but does not destroy its rocky core. To overcome this difficulty, we call attention to a high probability for Phaethon to have a satellite which was lost in the explosion. Its subsequent hypervelocity collision with the rocky core left led to the appearance of large (> 100 km) and numerous rocky bodies. Thus, as is often the case, the truth appears to lie between the extremes and such a synthesis combines the benefits of the both approaches.