October 26, 2011
American Center for Physics
College Park, MD
Date: Wednesday, October 26, 2011 (NOTE: DAY AND DATE)
Speaker: Dr. Doug Hamilton, University of Maryland
Topic: Where did the Galilean Satellites Form?
Time and Location: Talk starts at 1:00 pm with Q&A to follow. It will be held in one of the first floor conference rooms at the American Center for Physics, One Physics Ellipse, College Park, MD. This is located off River Road, between Kenilworth Ave. and Paint Branch Parkway.
Abstract: Resonances, both past and present, have profoundly affected Jupiter's four largest satellites.In their current configuration, the resonant interactions between Io, Europa, and Ganymede tap the spin energy of Jupiter to power the volcanoes on Io and to melt the icy shell of Europa. But when did the current configuration first arise? As with Earth's Moon, tidal interactions have been actively pushing the Galilean satellites radially outward for billions of years.So where did these satellites first form?Have they ever been deeper in resonance than they are now? Why is Europa's orbit tilted so much and Io's so little? My investigations of these interesting questions have been fruitful and are beginning to provide new answers. In particular, the requirement that certain resonances must have been encountered in the past, while others must have been avoided, puts strong constraints on the satellite formation distances
Biography: Doug Hamilton earned his Ph.D. from Cornell University in 1993. After two years as a postdoc at the Max Planck Institute in Heidelberg, Germany, Doug accepted an Assistant Professor position in the Astronomy Department at U. Maryland in 1995. He advanced through the ranks and is currently a full Professor. Doug was awarded the Urey Prize of the Division for Planetary Sciences in 1999, the U. Maryland Board of Regents Prize for scholarship in 2009, and a number of teaching awards over the past decade. Doug's research focuses on the origin and evolution of the Solar System, particularly on the intricate orbital dynamics of moons and rings. Doug is co-discoverer of the large Phoebe ring of Saturn in 2009 and of Pluto's 4th moon in 2011.