NASA scientists today announced the discovery of two Earth sized planets, named Kepler 20E and 20F. The planets were discovered by the Kepler space telescope team. "The first of the two planets has a diameter just 3 percent larger than the Earth, which makes it the closest object to Earth, in terms of size in the known universe," said Francois Fressin, Harvard-Smithsonian Center for Astrophysics, during a conference call to announce the major discovery.