Planet in sweet spot of Goldilocks zone for life

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This undated handout artist rendering provided by NASA shows Kepler-22b, a planet known to comfortably circle in the habitable zone of a sun-like star. (NASA/Ames/JPL-Caltech)

Updated: Tue Dec. 06 2011 10:53:41

CTVNews.ca Staff

Right now, it's one of the closest things Earth has to a doppelganger.

Using NASA's Kepler telescope, scientists have spotted a planet sitting outside the solar system that bears a striking resemblance to Earth in several ways.

It sits right in the middle of the "Goldilocks" zone, a habitable area that astronomers say is not too hot or cold – it's just right.

"This is actually a big step where we know if there is evidence of another Earth-like planet out there," Randy Attwood, the managing editor of Space Quarterly, told CTV's Canada AM on Tuesday.

Like Earth, the new planet circles a star that looks as if it could be the sun's twin. Astronomers also say the planet appears to have a 290-day year, just slightly short of Earth's 365.

Scientists also say the temperature on the surface of Kepler-22b, as it's been dubbed, sits around a comfortable 22 C.

But don't expect to make Kepler-22b a vacation destination any time soon.

"It is 600 light years away so just going there is not a possibility," said Attwood. "It would take millions of years to get there if we wanted to go."

There is another slight hitch. Scientists say the planet is too big for life to exist on the surface. From what NASA can tell, it's about 2.4 times the size of Earth.

Now, astronomers are tasked with figuring out if the surface of the planet is gaseous with some liquid or perhaps even rocky.

"Is it like a Mars planet or is it like Venus where it's cloudy and an extremely hot surface? Or is it Jupiter? We don't know," said Attwood.

Whatever it may be, Attwood notes that the mere discovery of a planet that resembles Earth in so many ways is a victory for NASA.

He adds that as the Kepler telescope continues to scan the skies, astronomers will likely discover more Earth-like planets.

"They have thousands of candidates -- they have about 50 earth candidates -- so as the Kepler mission goes on we will have more and more candidates," he said.