Formation of the Terrestrial Planets from a Narrow Annulus

Authors: Brad Hansen

(Submitted on 5 Aug 2009)

Abstract: We show that the assembly of the Solar System terrestrial planets can be successfully modelled with all of the mass initially confined to a narrow annulus between 0.7 and 1.0 AU.

With this configuration, analogues of Mercury and Mars often form from the collisional evolution of material diffusing out of the annulus under the scattering of the forming Earth and Venus analogues.

The final systems also possess eccentricities and inclinations that match the observations, without recourse to dynamical friction from remnant small body populations.

Finally, the characteristic assembly timescale for Earth analogues is rapid in this model, and consistent with cosmochemical models based on the $^{182}$Hf–$^{182}$W isotopes.

The agreement between this model and the observations suggests that terrestrial planet systems may also be formed in `planet traps’, as has been proposed recently for the cores of giant planets in our solar system and others.

Comments: 37 pages, 16 figures. to appear in ApJ

Subjects: Earth and Planetary Astrophysics (astro-ph.EP)

Cite as: arXiv:0908.0743v1 [astro-ph.EP]

Submission history

From: Brad Hansen [view email]

[v1] Wed, 5 Aug 2009 20:11:46 GMT (327kb)

http://arxiv.org/abs/0908.0743