The last decade has seen a huge increase in the number of known exoplanets (those outside of our own solar system). NASA’s Kepler mission has been responsible for a great deal of these planet discoveries in the last few years and today NASA revealed yet another wave of new planets discovered by the Kepler space observatory.

According to a paper set for publication in The Astrophysical Journal, Kepler data has been used to uncover the location of 715 new exoplanets. Astronomers used statistical techniques to seek out new planets in systems where more than one potential planet has already been detected by Kepler during its earliest observations.

“Four years ago, Kepler began a string of announcements of first hundreds, then thousands, of planet candidates – but they were only candidate worlds,” said Jack Lissauer, co-leader of the Kepler research team and a planetary scientist at NASA’s Ames Research Center. “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.”

More exciting than just the number is just how many of those planets could be orbiting in systems quite like our own. The 715 newly discovered planets were found in just 305 star systems. In addition, over 670 of them are smaller than Neptune, putting in them closer in size to Earth than to gas giants like Jupiter or Saturn.

Four of the newly discovered planets are smaller than 2.5 times the size of Earth and orbit within their system’s habitable zone, meaning that they could have liquid water on their surfaces. One planet in particular, Kepler-296f, is only twice the size of Earth and orbits a star half the size of the Sun, though astronomers do not yet know whether it is a rocky planet like Earth.

“From this study we learn planets in these multi-systems are small and their orbits are flat and circular – resembling pancakes – not your classical view of an atom,” said Jason Rowe, a co-leader of the Kepler research team and an astronomer at the SETI Institute. “The more we explore the more we find familiar traces of ourselves amongst the stars that remind us of home.”

Image via NASA