William J. Borucki

William Borucki conceived the idea and led the scientific and engineering teams for the Kepler observatory, a NASA mission that discovered 4706 exoplanet candidates (and counting) and confirmed over 2300 (and counting). The Kepler Mission detects repeated brightness decreases of a few parts in 100,000 due to planets passing in front of their parent stars, and from that information deduces the size, orbital period, and approximate temperature of each planet. Because of Borucki's leadership we now know that most stars have planets, small planets like Earth are common, and many are at the right temperature to enable life.