A Physical Model For Thermal Evolution And Metal Segregation In Early Planetesimals

Details A Physical Model For Thermal Evolution And Metal Segregation In Early Planetesimals A Physical Model For Thermal Evolution And Metal Segregation In Early Planetesimals

Dec 2007

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2007agufm.p41a0213m&link_type=abstract

American Geophysical Union, Fall Meeting 2007, abstract #P41A-0213

Physics

6024 Interiors (8147), 6040 Origin And Evolution, 6206 Asteroids: Satellites, 6223 Callisto

Scientific paper

Early core formation in planetesimals has been known for a long time from the existence of iron meteorites, however, the physical processes leading to core segregation are still a matter of debate. Until recently, the percolation of iron metal melt within a silicate solid matrix had not been considered because of the very high dihedral angle and because melting of silicate is often assumed necessary. Some recent studies have shown that iron metal melts migrate in a solid silicate matrix even at low porosity (e.g. Yoshino et al, 2003). We investigate the melting and percolation of iron-sulfide metal melts within a solid silicate matrix and its application to planetesimals using a spherically symmetric two-phase flow model coupled to the heat equation. The heat source for melting are the short-lived radionuclides (26Al and 60Fe). When the Fe-S eutectic is reached, percolation can start and metallic melt migrates to the center of the planetesimal due to the planetesimal's own gravity. We propose a complete model for segregation and obtain the resulting thermal state of the differentiated planetesimal. The short half life of both 26Al and 60Fe allows us to estimate a timescale for differenciation in the solar system. The varying degrees of differentiation of the different objects can be investigated within this framework. The case of icy satellites may be treated with the same approach and the largely undifferentiated nature of Callisto (one of Jupiter's largest satellites) can be used to constrain the conditions of its formation.

Affiliated with

Also associated with

No associations

Rating

A Physical Model For Thermal Evolution And Metal Segregation In Early Planetesimals does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with A Physical Model For Thermal Evolution And Metal Segregation In Early Planetesimals, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A Physical Model For Thermal Evolution And Metal Segregation In Early Planetesimals will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1406580