Geoff Marcy
Berkeley, California, United States
<p>I am a professor of astrophysics at the University of California at Berkeley. I serve as a co-investigator on the NASA Kepler mission to detect possibly habitable planets around other stars. Kepler has found over 3000 planets so far, many being nearly the size of Earth. We use the Keck telescope in Hawaii to measure the masses and densities of the planets, to determine if rock and water are major components of the planets.</p>