Candidates require follow-up observations to verify they are actual planets. Kepler also found six confirmed planets orbiting a sun-like star, Kepler-11. This is the largest group of transiting planets orbiting a single star yet discovered outside our solar system. artists impression of Kepler-11 solar system...

In one generation we have gone from extraterrestrial planets being a mainstay of science fiction, to the present, where Kepler has helped turn science fiction into today's reality, said NASA Administrator Charles Bolden. These discoveries underscore the importance of NASA's science missions, which consistently increase understanding of our place in the cosmos.

The discoveries are part of several hundred new planet candidates identified in new Kepler mission science data, released on Tuesday, Feb. 1. The findings increase the number of planet candidates identified by Kepler to-date to 1,235. Of these, 68 are approximately Earth-size; 288 are super-Earth-size; 662 are Neptune-size; 165 are the size of Jupiter and 19 are larger than Jupiter.

Of the 54 new planet candidates found in the habitable zone, five are near Earth-sized. The remaining 49 habitable zone candidates range from super-Earth size -- up to twice the size of Earth -- to larger than Jupiter..... ....

The fact that we've found so many planet candidates in such a tiny fraction of the sky suggests there are countless planets orbiting sun-like stars in our galaxy, said William Borucki of NASA's Ames Research Center in Moffett Field, Calif., the mission's science principal investigator. We went from zero to 68 Earth-sized planet candidates and zero to 54 candidates in the habitable zone....

some of which could have moons with liquid water.

Among the stars with planetary candidates, 170 show evidence of multiple planetary candidates. Kepler-11, located approximately 2,000 light years from Earth, is the most tightly packed planetary system yet discovered. All six of its confirmed planets have orbits smaller than Venus, and five of the six have orbits smaller than Mercury's. Kepler-11 has the fullest, most compact planetary system yet discovered beyond our own.

The only other star with more than one confirmed transiting planet is Kepler-9, which has three. The Kepler-11 findings will be published in the Feb. 3 issue of the journal Nature.

Kepler-11 is a remarkable system whose architecture and dynamics provide clues about its formation, said Jack Lissauer, a planetary scientist and Kepler science team member at Ames. These six planets are mixtures of rock and gases, possibly including water. The rocky material accounts for most of the planets' mass, while the gas takes up most of their volume.

By measuring the sizes and masses of the five inner planets, we determined they are among the lowest mass confirmed planets beyond our solar system.