Alex Filippenko is a world-renowned expert on exploding stars, black holes, and cosmology. Several major prizes have recognized his accomplishments, which are documented in about 770 research papers, and he is one of the world's most highly cited astrophysicists. An elected member of the National Academy of Sciences, he was the only person to have been a member of both teams that revealed the Nobel-worthy accelerating expansion of the universe. Voted the "Best Professor" on the Berkeley campus a record 9 times, Dr. Filippenko was also named the 2006 National Professor of the Year. He has produced 5 astronomy video courses with The Great Courses, coauthored an award-winning astronomy textbook, and appears in about 100 TV documentaries. In 2004, he was awarded the Carl Sagan Prize for Science Popularization. He enjoys playing tennis, hiking, skiing, snorkeling, and world travel, and he is addicted to observing total solar eclipses (13 so far).