Tuesday December 6, 2011 11:00 am
Kepler-22b: The most Earth-like planet ever found
Astronomers said Monday that NASA's Kepler spacecraft has discovered a far-off planet that orbits its Sun-like star at just the right distance to support life. Kepler-22b is about 2.4 times bigger than Earth and is located 600 light-years away from our planet.
"We're getting closer and closer to discovering the so-called 'Goldilocks planet,'" said Pete Worden, director of NASA's Ames Research Center, according to Space.com, referring to a habitable planet that is "just right" in meeting all the requirements for life.
Kepler-22b is pleasantly warm, with an average surface temperature of 72 degrees Fahrenheit, according to researchers. It orbits its star at the right distance for liquid water to exist.
The Kepler spacecraft has discovered 2,326 potential planets just 16 months into its planet-hunting mission. If those discoveries are confirmed, it brings the total number of planets scientists have discovered outside of our solar system to four times the 700 or so that were known to exist prior to Kepler's mission.
Kepler was launched in March 2009. The $600 million space observatory looks for small changes in a star's brightness that indicate a planet is transiting the star from the spacecraft's vantage point.
The spacecraft then sends its data back to Earth, where scientists conduct follow-up observations to determine if the candidate planets Kepler has observed are the real deal. Only about two dozen Kepler-discovered planets have been confirmed so far, but researchers say about 80 percent of the spacecraft's positive hits should wind up passing muster as planets.
Of the more than 2,000 candidate planets Kepler has discovered nearly 700 are larger than Earth, while 207 are about the same size as our home planet. The confirmation of planet status for Kepler-22b is almost certainly just the start for researchers—the Kepler spacecraft has also sent back data on nearly 50 more candidate planets that orbit within the habitable zones of their stars.
Back in September, data from the Kepler mission uncovered evidence of a circumbinary planet, or a planet that orbits two stars, which is reminiscent of Tatooine, the planet on which Star Wars character Luke Skywalker grew up.
Later that month, a Yale University-based online citizen science project known as Planet Hunters used data from NASA's Kepler mission to discover what might be two exoplanets.
This article, written by Damon Poeter, originally appeared on PCMag.com and is republished on Gear Live with the permission of Ziff Davis, Inc.