NASA announced on Monday, Jan. 10 that the Kepler mission had discovered Kepler-10b, a rocky planet a little bigger than Earth orbiting a star called Kepler-10. It is only 1.4 times the size of Earth and is the smallest planet NASA has found outside our solar system.
"All of Kepler's best capabilities have converged to yield the first solid evidence of a rocky planet orbiting a star other than our sun," said Natalie Batalha of NASA in a press release. She is the deputy science team lead for Kepler at NASA's Ames Research Center in Moffett Field, Calif., and wrote a paper on the discovery, which Astrophysical Journal accepted.
The scientists identified Kepler-10b and calculated its size by measuring the decrease in Kepler-10’s brightness when Kepler-10b passes in front of it.
Scientists think Kepler-10b cannot support life because it is too close to its star to have liquid water. They think any planet with life must be in what they call the “habitable zone,” with liquid water and moderate temperatures.
"The discovery of Kepler 10-b is a significant milestone in the search for planets similar to our own," said Douglas Hudgins, Kepler program scientist at NASA Headquarters in Washington in a news release. "Although this planet is not in the habitable zone, the exciting find showcases the kinds of discoveries made possible by the mission and the promise of many more to come," he said.