Gravitational instabilities in satellite disks and formation of regular satellites
Abstract
The formation of local planetesimals around Jupiter and Saturn is examined, with consideration given to the onset of gravitational instabilities in a two fluid system (gas and solid particles coupled by viscosity). This theory takes into account the fact that solid particles, even before the development of instabilities, are in disequilibrium with the gas, settling toward the mid-plane and spiraling. Satellite disk evolution is discussed, with the assumption that the formation of the accretion disk and that of the central body are coupled. Evolution of the planetesimals is characterized by collisional accretion and orbital decay, and occurs by means of gravitational instabilities in an evolving satellite disk. Planetesimal masses are shown to be 4 x 10 to the 15th to 2 x 10 to the 17th grams. Time scales for the various processes are estimated, and a possible mechanism for the formation of regular satellites is described.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- June 1981
- Bibcode:
- 1981A&A....99..255C
- Keywords:
-
- Jupiter (Planet);
- Natural Satellites;
- Planetary Evolution;
- Planetary Gravitation;
- Saturn Satellites;
- Systems Stability;
- Gas-Solid Interfaces;
- Gravitational Effects;
- Planetary Mass;
- Lunar and Planetary Exploration