Learn about NASA’s Kepler Mission in this video from NOVA: Alien Planets Revealed. The Kepler space telescope is designed to look for planets in one small patch of sky that contains about 4.5 million stars. Kepler is designed to detect the dimming that occurs when a planet transits a star. Animations illustrate the analogy of how a moth flying in front of a spotlight causes a subtle change in brightness: the bigger the moth, the more light it blocks. Patterns of changes in the brightness of each star indicate orbiting planets. By June 2010, just 15 months after its launch, Kepler had found over 700 potential planets.
Visit the program page here.