Impacts
Earth Science is currently undergoing its next major revolution after plate tectonics. Overturning more than a century of conventional wisdom that excluded sudden catastrophes from Earth History, recent work has demonstrated that asteroid and comet impacts play major roles in our Solar System. From the impact-scarred faces of the Moon and Mars to the death of the dinosaurs, impacts have set the course of planetary evolution.
We now believe that the Moon itself was born in a planetary scale impact between the Earth and a Mars-size protoplanet about 4.5 billion years ago. Impacts have brought us samples of Mars and the Moon in the form of meteorites and may have transferred life from Earth to Mars or vice versa. Even now, asteroids that cross the Earth’s orbit are being cataloged as potential threats to our civilization. The study of meteorite impacts has evolved from the obscure pastime of a few visionary scientists a half-century ago to the forefront of modern research.
Listen to ‘Impacts’ in our series of podcasts to hear Jay Melosh and two colleagues discuss their work in settling the debate over the Chicxulub impact crater and its role in the extinction of dinosaurs.
Speaker
Jay Melosh, Purdue University
Biography
H. J. Melosh is a Distinguished Professor in the Department of Earth and Atmospheric Sciences, Purdue University, West Lafayette, IN, USA. He received an AB degree in Physics from Princeton University in 1969 and a PhD in Physics and Geology from Caltech in 1973. His principal research interests are impact cratering, planetary tectonics, and the physics of earthquakes and landslides. His recent research includes studies of the giant impact origin of the moon, the K/T impact that extinguished the dinosaurs, the ejection of rocks from their parent bodies and the origin and transfer of life between the planets. He is a science team member of NASA’s Deep Impact mission that successfully cratered comet Tempel 1 on July 4, 2005.
Professor Melosh is a Fellow of the Meteoritical Society, the Geological Society of America the American Geophysical Union and American Association for the Advancement of Science. He was awarded the Barringer Medal of the Meteoritical Society in 1999, the Gilbert prize of the Geological Society of America in 2001 and the Hess Medal of the American Geophysical Union in 2008. He was a Guggenheim Fellow in 1996-1997 and a Humboldt Fellow at the Bavarian Geological Institute in Bayreuth, Germany, in 2005-2006. Asteroid #8216 was named “Melosh” in his honor. He was elected to the U.S. National Academy of Sciences in 2003.
He has published approximately 170 technical papers, edited two books and is the author of a major monograph, Impact Cratering: A Geologic Process. He is currently preparing a new book “Planetary Surface Processes” under contract to Cambridge University Press.
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