#OTD in 2011, we discovered Kepler-20e, the first planet beyond our solar system smaller than Earth. In all, we've confirmed six exoplanets in the system orbiting a Sun-like star more than 900 light-years from Earth. exoplanets.nasa.gov/resources/… #NASAExoplanets
This artist's animation flies through the Kepler-20 star system, where NASA's Kepler mission discovered the first Earth-size planets around a star beyond our own.
