Photophoretic transport as a carrier of hot minerals found in Comet 81 P/Wild2
Abstract
A time-dependent model of the solar nebula is used to describe the outward transport of hot mineral aggregates from locations in the warm inner regions of the nebula under the influence of photophoresis. We show that there is a direct dependence between the size of the gap initially assumed to exist in the inner solar nebula and the heliocentric distance to which the aggregates are likely to drift. We demonstrate that, despite a significant contribution to the opacity of the disk resulting from Rayleigh scattering by hydrogen, photophoresis can be considered as a transport mechanism leading to the presence of hot minerals in comets. This mechanism can lead to an influx of hot minerals in the formation regions of the main cometary reservoirs, implying a potential "dust-loading" of bodies from these populations. This scenario is compatible with the detection of crystalline silicates in a growing number of comets and also with the recent identification of CAIs in the samples returned from Comet 81P/Wild 2 by the Stardust mission.
- Publication:
-
SF2A-2007: Proceedings of the Annual meeting of the French Society of Astronomy and Astrophysics
- Pub Date:
- July 2007
- Bibcode:
- 2007sf2a.conf..416M