Advances in exoplanet science from Kepler.

Numerous telescopes and techniques have been used to find and study extrasolar planets, but none has been more successful than NASA's Kepler space telescope. Kepler has discovered most of the known exoplanets, the smallest planets to orbit normal stars and the planets most likely to be similar to Earth. Most importantly, Kepler has provided us with our first look at the typical characteristics of planets and planetary systems for planets with sizes as small as, and orbits as large as, those of Earth.