Earth 2.0 New planet may hold LIFE

Kepler 22b

The most Earth-like planet ever discovered is circling a star 600 light years away, a key finding in an ongoing quest to learn if life exists beyond earth, scientists said on Monday. The planet, called Kepler-22b, joins a list of more than 500 planets found to orbit stars beyond our solar system. It is the smallest and the best positioned to have water on its surface — one among the ingredients necessary for life on Earth.
"We are homing in on the true Earth-sized, habitable planets," said San Jose State University astronomer Natalie Batalha, deputy science team lead for Nasa's Kepler Space Telescope that discovered the star. The telescope, which was launched three years ago, is staring at about 150,000 stars in the constellations Cygnus and Lyra, looking for faint and periodic dimming as any circling planets pass by, relative to Kepler's line of sight.

Kepler 22 system - A NASA artist's conception illustrates Kepler-22b, a planet in the habitable zone of a sun-like star. Astronomers do not know whether life actually exists on the planet, but they say the conditions are right

This is the first detection of a potentially habitable world orbiting a sun-like star, scientists reported in their findings. Kepler-22b is 600 light years away. It is about 2.4 times the radius of Earth and sits squarely in its star's so-called habitable zone, the region where liquid water could exist on the surface. Studies are under way to determine if the planet is solid, like Earth, or more gaseous like Neptune.

Artist's impression of the Kepler-10 star system near the Cygnus and Lyra constellations. Kepler-10b is the smallest known planet outside our solar system (dark spot against the sun). It was discovered in Jan 2011

If Kepler-22b has a surface and a cushion of atmosphere similar to Earth's, it would be about 72 degrees Fahrenheit or 22 degrees Celsius, about the same as a spring day in Earth's temperate zone.