Impact specialist to discuss catastrophic collisions in space


University of Arizona’s planetary scientist and impact specialist H. Jay Melosh is this year’s recipient of the Eugene Shoemaker Memorial Award presented by the BEYOND Center for Fundamental Concepts in Science at Arizona State University.

As part of the honor, Melosh will deliver the annual Shoemaker Memorial lecture at 7:30 p.m. March 4 in Armstrong Hall’s Great Hall on ASU’s Tempe campus. The title of his talk is “Our Catastrophic Solar System: Impacts and the Latest Revolution in Earth Science.”

“From the impact-scarred faces of the moon and Mars, to the death of the dinosaurs, impacts have set the course of planetary evolution,” says Melosh. “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.”

Melosh, a Regents’ Professor of Planetary Science at UA’s Lunar and Planetary Lab, is a science team member of NASA’s deep impact mission that successfully cratered comet Tempel 1 on July 4, 2005.

“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,” Melosh says. “Even now, asteroids that cut across the Earth’s orbit are being catalogued 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,” Melosh says.

The transfer of life between Mars and Earth is something that Shoemaker himself speculated on in 1965, according to Melosh.

“It is particularly fitting to present the Shoemaker Award to Jay Melosh in the year of Darwin’s bicentenary, because Melosh was the first person to recognize that cosmic collisions can transfer life between Mars and Earth. It is now generally acknowledged that microbes can hitchhike on rocks blasted into space by big impacts, and travel across the solar system,” says Paul Davies, professor and director of the BEYOND Center in ASU’s College of Liberal Arts and Sciences.

Shoemaker was known for his pioneering research with his wife, Carolyn, in the field of asteroid and comet impacts. Last year’s recipient was Walter Alvarez, geologist and author of “T. rex and the Crater of Doom.” In 2007, Apollo 17 astronaut Harrison Schmitt was the first recipient of the award.

Among many other contributions to the field of astronomy, Shoemaker, his wife, and their friend David Levy, discovered a comet that collided with Jupiter in 1994. That comet was named the Shoemaker-Levy 9.

The Eugene Shoemaker Memorial Award is presented each year to a leading scientist in honor of his or her life and work.

This year’s recipient, Melosh, has received the Hess Medal from the American Geophysical Union in 2008, the Gilbert Prize from the Geological Society of America in 2001 and the Barringer Medal from the Meteoritical Society in 1999. He was a Guggenheim Fellow and a Humboldt Fellow at the Bavarian Geological Institute. He was elected to the U.S. National Academy of Sciences in 2003. The asteroid 8216 was named “Melosh” in his honor.

Melosh also is a fellow of the Meteoritical Society, Geological Society of America, American Geophysical Union, and American Association for the Advancement of Science.

His principal research interests include impact cratering, planetary tectonics, and the physics of earthquakes and landslides. His recent research includes the giant impact origin of the moon, Cretaceous-Tertiary boundary impact that extinguished the dinosaurs, ejection of rocks from their parent bodies, and origin and transfer of life between the planets.

Melosh received a doctorate in physics and geology from the California Institute of Technology and a bachelor’s degree in physics from Princeton University. He has published more than 170 technical papers, edited two books and is the author of “Impact Cratering: A Geologic Process.” He is writing a new book titled “Planetary Surface Processes.”

The Eugene Shoemaker Memorial Lecture is free and open to the public. Seating is limited and is on a first-come, first-served basis. C.A.R.T. services will be available. More information at 480-965-3240 or http://beyond.asu.edu. Online maps of the Tempe campus and parking structures at: www.asu.edu/map.

The BEYOND Center for Fundamental Concepts in Science is a pioneering international research center established in 2006 at ASU. This “cosmic think tank” is specifically dedicated to confronting the big questions raised by advances in fundamental science, and facilitating new research initiatives that transcend traditional subject categories.