John Bahcall has held positions at Indiana University, Caltech, and the Institute for Advanced Study. He is currently the Richard Black Professor of Natural Sciences at the Institute for Advanced Study and Visiting Lecturer with rank of Professor at Princeton University. He has received numerous awards, including the National Medal of Science and the Hans Bethe Prize from the American Physical Society in 1998. He has written several books, including Unsolved Problems in Astrophysics and The Decade of Discovery in Astronomy and Astrophysics. Raymond Davis, Jr. retired from a prestigious career at Brookhaven Lab, a multi-program national laboratory operated for the U.S. Dept. of Energy, to become a research professor at the University of Pennsylvania in 1984. A member of the National Academy of Sciences, Davis has won numerous scientific awards, including the Tom W. Bonner Prize in 1988 and the W.K.H. Panofsky Prize in 1992. Peter Parker is Professor of Physics and Astronomy at Yale University in the Wright Nuclear Structure Laboratory. Since his graduate student days, Parker has performed laboratory experiments to study nuclear reactions that are important in stars. Alexei Smirnov is senior research scientist at the International Center for Theoretical Physics (Trieste, Italy), and is also the leading research scientist at the Institute for nuclear research of the Russian Academy of Sciences in Moscow. Smirnov is a co-discoverer of the MSW (Mikhayev-Smirnov-Wolfenstein) effect, which describes how matter can enhance the flavor conversion of neutrinos, and is a leading particle phenomenologist. Roger Ulrich is professor of Astronomy at the University of California, Los Angeles, and is active in the study of the solar interior using theoretical and observational methods. He first interpreted the periodic fluctuations observed on the solar surface as the solar analogue of terrestrial seismic waves.