Lunar and Planetary Institute

LPI Seminar Series

Effective January 1, 2011, LPI seminars will be held on Fridays.

LPI seminars are held from 3:30–4:30 p.m. in the Lecture Hall at USRA, 3600 Bay Area Boulevard, Houston, Texas. Refreshments are served at 4:30 p.m. For more information, please contact Georgiana Kramer (phone: 281-486-2141; e-mail: or Patricia Craig (phone: 281-486-2144; e-mail: A map of the Clear Lake area is available here. This schedule is subject to revision.

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See also the Rice University Department of Physics and Astronomy Colloquia and the Department of Earth Science Colloquia pages for other space science talks in the Houston area.

March 2017

Thursday, March 2, 2017 - Lecture Hall, 3:30 PM

David Patrick O'Brien, Planetary Science Institute
The formation and evolution of the inner Solar System
In the "classical" model of terrestrial planet formation, planetesimals and planetary embryos accrete together to form the planets, with Jupiter and the other giant planets undergoing minimal migration during that time. The asteroid belt is an excited and depleted remnant of the material originally lying interior to Jupiter. This model can broadly reproduce many of the characteristics of the inner Solar System, but faces difficulties in matching some key details, in particular the small size of Mars compared to Earth and Venus. In the newer "Grand Tack" scenario, the giant planets undergo substantial radial migration during the early stages of terrestrial planet formation. This scenario provides a better match to the small size of Mars, and populates the asteroid belt with material scattered from much wider range of distances from the Sun. I will discuss these models in detail, in particular focusing on the implications for the delivery of water and other materials to the terrestrial planets, and the implications for the taxonomic distribution of asteroids and the collisional/dynamical histories recorded in the meteorite record.


Previous Seminars

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