Exoplanets & Exomoons

Terrestrial Planet Formation at Home and Abroad

By Keith Cowing
December 9, 2013
Filed under
Terrestrial Planet Formation at Home and Abroad

We review the state of the field of terrestrial planet formation with the goal of understanding the formation of the inner Solar System and low-mass exoplanets.

We review the dynamics and timescales of accretion from planetesimals to planetary embryos and from embryos to terrestrial planets.

We discuss radial mixing and water delivery, planetary spins and the importance of parameters regarding the disk and embryo properties. Next, we connect accretion models to exoplanets. We first explain why the observed hot Super Earths probably formed by in situ accretion or inward migration. We show how terrestrial planet formation is altered in systems with gas giants by the mechanisms of giant planet migration and dynamical instabilities. Standard models of terrestrial accretion fail to reproduce the inner Solar System.

The “Grand Tack” model solves this problem using ideas first developed to explain the giant exoplanets. Finally, we discuss whether most terrestrial planet systems form in the same way as ours, and highlight the key ingredients missing in the current generation of simulations.

Sean N. Raymond, Eiichiro Kokubo, Alessandro Morbidelli, Ryuji Morishima, Kevin J. Walsh (Submitted on 5 Dec 2013)

Comments: 27 pages, 9 figures, 2 tables. Accepted for publication as a chapter in Protostars and Planets VI, University of Arizona Press (2014), eds. H. Beuther, R. Klessen, C. Dullemond, Th. Henning Subjects:

Earth and Planetary Astrophysics (astro-ph.EP); Solar and Stellar Astrophysics (astro-ph.SR)

Cite as: arXiv:1312.1689 [astro-ph.EP] (or arXiv:1312.1689v1 [astro-ph.EP] for this version)

Submission history From: Sean Raymond [v1] Thu, 5 Dec 2013 21:00:01 GMT (1364kb)

Explorers Club Fellow, ex-NASA Space Station Payload manager/space biologist, Away Teams, Journalist, Lapsed climber, Synaesthete, Na’Vi-Jedi-Freman-Buddhist-mix, ASL, Devon Island and Everest Base Camp veteran, (he/him) 🖖🏻