Santa Claus has brought an early Christmas gift to the earthlings - NASA has discovered an Earth-like planet outside our solar system whose distance from its on star makes it "habitable."

Earth's twin Kepler 22-b is a habitable planet with a moderate surface temperature of about 72 Fahrenheit (22C).

This is the first time NASA has found a planet, which is right in the middle of the habitable zone, and orbits a sun-like star every 290 days.

Kepler 22-b, about 600 light-years from Earth, has become the latest find of NASA even as man's hunt for extraterrestrial life and quest of finding potential new colonies for mankind beyond our solar system grow.

Forty-eight of 1,094 planet candidates, found since February 2011, orbit in the so-called "Goldilocks zone" and 10 of them nearly have the same size as that of Earth. Kepler 22-b is about 2.4 times the size of our home planet.

"It's conceivable that any - or many - of these 48 habitable zone candidates, or their moons, could have life," the principal investigator of NASA's Kepler space telescope, William Borucki, said to Wired.com.

The first transit of Kepler 22-b was captured three days after NASA declared the spacecraft operationally ready. The planet has been seen three times crossing in front of its star since it was first seen in 2009.

Astronomers suspect that Kepler 22-b is made of mostly of rock, gas or liquid, and may contain plenty of compressed ice or even be blanketed by a global ocean.

Kepler takes a new step forward to NASA's science missions: to answer questions about Earth in the universe and questions about extraterrestrial life.