Alex Filippenko is Professor of Astronomy at the University of California, Berkeley. He received his Bachelor's degree in Physics from the University of California, Santa Barbara, and earned his Ph.D. in Astronomy from the California Institute of Technology. Dr. Filippenko's research accomplishments, documented in more than 500 scientific publications and 600 abstracts and astronomical circulars, are among the most highly cited in the world. He has been recognized with several major awards, including the 1992 Newton Lacy Pierce Prize of the American Astronomical Society, the 1997 Robert M. Petrie Prize of the Canadian Astronomical Society, and the 2007 Richtmyer Memorial Award of the American Association of Physics Teachers. He was a Guggenheim Fellow in 2001 and a Phi Beta Kappa Visiting Scholar in 2002. Science magazine credited Professor Filippenko and his international team of astronomers with the top "Science Breakthrough of 1998" for research on exploding stars (supernovae), which shows that the universe is expanding at an accelerating rate, propelled by mysterious "dark energy." Professor Filippenko also leads the world's most successful robotic search for exploding stars. At UC Berkeley, Dr. Filippenko's teaching awards include the Donald S. Noyce Prize for Excellence in Undergraduate Teaching in the Physical Sciences and the Distinguished Teaching Award. He was also voted the Best Professor on Campus in student polls in 1995, 2001, 2003, 2004, and 2006. At the end of 2006, he was honored nationally as the "Outstanding Doctoral and Research Universities Professor of the Year" by the Carnegie Foundation for the Advancement of Teaching and the Council for Advancement and Support of Education. Dr. Filippenko is coauthor of The Cosmos: Astronomy in the New Millennium, now in its third edition, and winner of the 2001 Texty Excellence Award for best new textbook in the physical sciences.