With a single announcement, NASA is nearly doubling the number of known planets outside our solar system. In a pair of papers published today, NASA has revealed the discovery of 715 new and verified planets, bringing the total number of known exoplanets up to 1,700. The planets were found orbiting around 305 different stars, forming multiple-planet systems with constructions much like our own. The planets too bear some resemblance to ours: 95 percent of them are no more than four times larger than Earth.

But while the new planets' sizes and systems may be familiar, they aren't necessarily just like Earth. NASA found that only four of the planets orbit inside of their sun's habitable zones. Still, its researchers are excited to see these similar characteristics at all. "That these new planets and solar systems look somewhat like our own, portends a great future when we have the James Webb Space Telescope in space to characterize the new worlds," John Grunsfeld, a NASA administrator, says in a statement.

The new bodies were discovered by using a statistical technique that pointed to systems that were likely to hold multiple planets at once. From there, researchers at NASA's Ames Research Center analyzed the stars with more than one potential planet and worked through them to verify the 715 planets announced today.

"Four years ago, Kepler began a string of announcements of first hundreds, then thousands, of planet candidates — but they were only candidate worlds," Jack Lissauer, one of the Ames research team's leaders, says in a statement. "We've now developed a process to verify multiple planet candidates in bulk to deliver planets wholesale, and have used it to unveil a veritable bonanza of new worlds."

The discovery is expected to help the study of planet formation and planetary system configuration. While NASA's Grunsfeld points to the upcoming Webb telescope as a necessity for deeper analysis, we may still see more out of the Kepler mission. This discovery came out of data collected by the Kepler telescope during its first two years of activity, from 2009 to 2011; and while it looked like Kepler would have to be abandoned back in August, NASA is now looking to give it a second life in hopes of discovery even more new planets.