Geoff Marcy is a professor of Astronomy at the University of California at Berkeley. He earned his  Ph. D. in astronomy and astrophysics from the University of California, Santa Cruz, in 1982. His research has focused on the detection of extrasolar planets and brown dwarfs. His team has discovered over 110 extrasolar planets, allowing study of their masses and orbits. Among the planets discovered are the first multiple-planet system, the first Saturn-mass planet, the first Neptune-mass planet and the first transiting planet. Ongoing work is designed to study the mass distribution of planets and the eccentricity of their orbits. He is participating in the Berkeley's new "Center for Integrative Planetary Science," designed to study the formation, geophysics, chemistry and evolution of planets. Internet: http://astro.berkeley.edu/~gmarcy/