[Baps] Malhotra, CfA ITC Colloquium, Tue. Sept. 13 12:30 PM

[Sarah T. Stewart-Mukhopadhyay]

CfA Institute for Theory and Computation Colloquia
TUESDAY, SEPTEMBER 13
12:30 pm, Pratt Conference Room
"The Origin of Planetary Impactors in the Inner Solar system"
Prof. Renu Malhotra
University of Arizona. 
Abstract: The Moon and all the terrestrial planets were resurfaced during a
period of intense impact cratering that occurred between the time of their
accretion, ~4.5 billion years ago, and ~3.85 billion years ago: the crater
record and radiometric dating of lunar rocks attests to this conclusion.
However, identifying the source(s) of those planetary impactors has proven
elusive; speculations have included comets, asteroids, and fragments of a
shattered 'large planetesimal'. I will describe compelling new evidence that
the source of the impactors was the main asteroid belt, and that the
dynamical mechanism that caused the so-called 'Late Heavy Bombardment' ~3.9
billion years ago was unique in the history of the Solar System and distinct
from the processes producing the flux of objects that currently hit
planetary surfaces. The Late Heavy Bombardment was a rain of asteroids
dynamically ejected from the main asteroid belt due to the effects of
orbital migration of Jupiter and Saturn. 
http://www.cfa.harvard.edu/cfa/calendar/latest.html
http://cfa-www.harvard.edu/tad/events/

Directions/map:
http://cfa-www.harvard.edu/mapsdir.html
http://cfa-www.harvard.edu/images/cfa_60Garden.jpg


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