Kavli Institute For Theoretical Physics
The KITP Public Lecture Series

You Say You Want a Revolution: Planetary Systems Different from Our Own

sponsored by Friends of KITP

For the first time, we humans are surveying the nearest stars to detect planetary systems. The key question is whether our Solar System is special in some way that might explain the proliferation of life on the third planet. Our search is revealing the masses and orbits of the planets around nearby stars.

Remarkably, the properties of the 60 planets found so far differ from the nine planets in our Solar System. The possibility looms that some (and perhaps most) planetary systems have different architectures than our Solar System. Most of the planets reside in elliptical orbits rather than circular. Such planets will suffer wild temperature fluctuations as they travel close to and far from the host star. The chemistry and atmospheres on these planets are significantly altered by the orbit and mass of the planet. Planets the size of Earth remain undetectable, however, various pieces of evidence suggest that Earths are common.

Geoffrey Marcy is Professor of Astronomy at the University of California, Berkeley. Before moving to Berkeley in 1997, he was a Distinguished University Professor at San Francisco State University. Dr. Marcy\'s research is focused on the detection of extrasolar planets and brown dwarfs. His team has discovered several dozen extrasolar planets, allowing study of their masses, radii, and orbits. Among the planets is the first multiple-planet system, the first Saturn candidates, and the first transiting planet. Ongoing work is designed to study the mass distribution of planets and the eccentricity of their orbits. The 5-year goal is to find Jupiter analogs around other stars.

His discovery of extrasolar planets was just recognized by the National Academy of Science by the awarding of the Henry Draper Medal to Marcy and his long-time collaborator, Paul Butler. Marcy was California Scientist of the Year in 2000 and received the Manne Siegbahn Award from the Physics Committee of the Swedish Academy in 1996. Dr. Marcy is the first director of the Center for Integrative Planetary Science at UC-Berkeley, designed to study the formation, geophysics, chemistry and evolution of planets.