MINIMUM MASS SOLAR NEBULAE AND PLANETARY MIGRATION

The Minimum Mass Solar Nebula (MMSN) is a protoplanetary disk that contains the minimum amount of solids necessary to build the planets of the solar system. Assuming that the giant planets formed in the compact configuration they have at the beginning of the "Nice model," Desch built a new MMSN. He finds a decretion disk, about 10 times denser than the well known Hayashi MMSN. The disk profile is almost stationary for about 10 million years. However, a planet in a protoplanetary disk migrates. In a massive, long-lived disk, this issue has to be addressed. With numerical simulations, we show that the four giant planets of the solar system could not survive in this disk. In particular, Jupiter enters the type III, runaway regime, and falls into the Sun like a stone. Known planet-planet interaction mechanisms to prevent migration fail in this nebula, in contrast to the Hayashi MMSN. Planetary migration constrains the construction of an MMSN. We show how this should be done self-consistently.