Ten new Earth-size planets that could host liquid water and might have rocky surfaces have been found beyond our own modest solar system by NASA’s Kepler spacecraft, scientists said Monday.
The new planets’ existence must still be double-checked. But Kepler’s latest haul — which includes a planet that is only slightly larger than Earth and receives the same amount of energy from its sun as Earth — is the latest triumph for Kepler, which has spotted roughly 80% of the planets orbiting stars other than our sun.
Because of their potential for hosting life, the 10 Earth-size planets are the most glamorous of the newly announced planets from Kepler. But those 10 were joined by an additional 209 more garden-variety planets that are unlikely to be hospitable to life because they are too gassy, too hot, too cold or otherwise unlike the only known planet to host life: Earth.
Kepler’s steering wheels broke down several years ago, leaving it unable to scan the stars using the same technique that has yielded so many new worlds. Monday’s announcement of a long list of new planets credited to Kepler will be the last.
“Yeah, it feels a bit like the end of an era,” said Susan Thompson, a Kepler researcher at the SETI Institute. “But actually I see it as a new beginning. … I’m really excited to see what people are going to do with this catalog.”