Washington: US space agency NASA said Wednesday its Kepler spacecraft has verified the existence of 715 more planets orbiting stars outside the solar system.
The latest discovery brings the confirmed count of planets beyond the solar system to nearly 1,700, Jack Lissauer, a planetary scientist at NASA's Ames Research Center told a press teleconference, Xinhua reported.
"We've almost doubled just today the number of planets known to humanity," Lissauer said.
These newly-verified worlds orbit 305 stars, meaning many are in "multiple-planet systems much like our own solar system," NASA said.
Nearly 95 percent of these planets are smaller than Neptune, which is almost four times the size of Earth, it said.
Four of these new planets are less than 2.5 times the size of Earth and orbit in their sun's habitable zone, where water can exist in liquid form, it said.
"The Kepler team continues to amaze and excite us with their planet hunting results," said John Grunsfeld, associate administrator for NASA's Science Mission Directorate, in a statement.
NASA said the verification of the existence of a planet is "a laborious planet-by-planet process" in the past but the team has a new powerful statistical technique that can be applied to many planets at once.