NASA's Kepler Space Telescope Confirms Alien Planet in Habitable Zone

摘要

NASA's planet-hunting Kepler spacecraft has confirmed the discovery of its first alien world in its host star's habitable zone - that just-right range of distances that could allow liquid water to exist-and found more than 1,000 new exoplanet candidates, researchers here announced Dec. 5. The new finds bring the Kepler space telescope's total haul to 2,326 potential planets in its first 16 months of operation. These discoveries, if confirmed, would quadruple the current tally of worlds known to exist beyond our solar system, which recently topped 700. The potentially habitable alien world, a first for Kepler, orbits a star very much like Earth's sun. The discovery brings scientists one step closer to finding a planet like our own - one that could conceivably harbor life, scientists said. "We're getting closer and closer to discovering the so-called Goldilocks planet," Pete Warden, director of NASA's Ames Research Center here, said during a news conference. The newfound planet in the habitable zone is called Kepler-22b. It is located about 600 light-years away, orbiting a sun-like star. Kepler-22b's radius is 2.4 times that of Earth, and the two planets have roughly similar temperatures. If the greenhouse effect operates- there similarly to how it does on Earth, the average surface temperature on Kepler-22b would be 22 degrees Celsius.