NASA's Kepler Comes Roaring Back

NASA's Kepler Comes Roaring Back with 100 New Exoplanet Finds

by Sarah Lewin, Staff Writer   

The artist's illustration shows NASA's planet-hunting Kepler spacecraft operating in its second-chance K2 mission. Credit: NASA Ames/JPL-Caltech/T Pyle View full size image

KISSIMMEE, Fla. —
NASA's Kepler spacecraft has bounced back nicely from the malfunction that ended its original exoplanet hunt more than two years ago.

Kepler has now discovered more than 100 confirmed alien planets during its second-chance K2 mission, researchers announced today (Jan. 5) here at the 227th Meeting of the American Astronomical Society (AAS).

The $600 million Kepler mission launched in March 2009, tasked with determining how commonly Earth-like planets occur throughout the Milky Way galaxy. Kepler has been incredibly successful, finding more than 1,000 alien worlds to date, more than half of all exoplanets ever discovered.

The first five K2 campaigns, which each looked at a different part of the sky, "have produced over 100 validated planets," Ian Crossfield, an astronomer at University of Arizona, said today during a presentation at the AAS meeting. "This is a validation of the whole K2 program's ability to find large numbers of true, bona fide planets."

Crossfield said that Kepler observed more than 60,000 stars and found 7,000 transitlike signals during the first five 80-day observation campaigns. A validation process whittled some of these signals down to planet candidates, and then finally to validated planets, each of which has just a 1 percent chance of being a false positive, Crossfield added.

He also noted that K2 found more false positives among larger planets than small ones, and that more than half of the false positives were in multiplanet systems.

While planning K2, Kepler principal investigator Bill Borucki, who retired this past July after a 53-year NASA career, said the new mission could find "dozens, or maybe even hundreds" of exoplanets. Now, K2 has racked up more than 100, and lots of exciting extrasolar systems will likely be spotted in the future, Crossfield said.

"We're only a quarter or so of the way done, we hope," he said.

Email Sarah Lewin at slewin@space.com or follow her @SarahExplains. Follow us @Spacedotcom, Facebook and Google+. Originally published on Space.com.