  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 the majority of known exoplanets, the smallest
planets to orbit normal stars, and the worlds most likely to be similar to our
home planet. Most importantly, Kepler has provided our first look at typical
characteristics of planets and planetary systems for planets with sizes as
small as and orbits as large as those of the Earth.
