The Kepler Space Telescope has been in orbit looking for planets around other stars since 2009, and it's started to find some startlingly interesting solar systems out there.
Today, the Kepler team announced the discovery of star system Kepler 62, a group of five planets circling a red star, two of which may be capable of supporting life. That doubles the number of Earth-like planets in the habitable zone that Kepler has confirmed in the cosmos. And they're the smallest, and therefore closest to Earth size, that astronomers have detected. The system is 1,200 light years away.
This is remarkably exciting. Not only do we know about two more Earth-like planets out there, but they're in the same solar system! That sent at least one scientist into the kind of reverie that I've been having since I heard the news.
"Imagine looking through a telescope to see another world with life just a few million miles from your own, or having the capability to travel between them on regular basis," Kepler team member Dimitar Sasselov of Harvard told New Scientist. "I can't think of a more powerful motivation to become a space-faring society."
While scientists have found that our galaxy is teeming with planets, it takes longer to detect planets that take a long time to orbit their suns. That's because Kepler detects planets when they pass in front of their stars. If a planet takes a couple hundred Earth-days to go around its sun, the scientists need several years to gather several transits, as they're known.
NASA's Bill Borucki, the mission's principal scientific investigator and a tireless proponent of this misson for years, was understandably excited about the discoveries.
"The detection and confirmation of planets is an enormously collaborative effort of talent and resources, and requires expertise from across the scientific community to produce these tremendous results," Borucki said in a NASA release. "Kepler has brought a resurgence of astronomical discoveries and we are making excellent progress toward determining if planets like ours are the exception or the rule."
The search for planets like our own is one of the science's most exciting frontiers, and after years of waiting for the discovery of Earth-like planets, we're finally getting them. This one was published in the journal Science. It's also worth noting that Borucki's team announced another planetary system surrounding a star like our own that harbors one Earth-like planet. It was a big day for those awaiting news of other planets capable of supporting life.