Kepler 22b: An Almost Earth Orbiting an Almost Sun - Nasa APOD 7 Dec 2011

 

Illustration Credit: NASA / Ames / JPL-Caltech

Explanation: It’s the closest match to Earth that has yet been found. Recently discovered planet Kepler 22b has therefore instantly become the best place to find life outside our Solar System. The planet's host star, Kepler 22, is actually slightly smaller and cooler than the Sun, and lies 600 light-years from Earth toward the constellation of the Swan (Cygnus). The planet, Kepler 22b, is over twice the radius of the Earth and orbits slightly closer in, but lies in the habitable zone where liquid water could exist on the surface. Pictured above is an artist’s depiction of how Kepler 22b might appear to an approaching spaceship, in comparison to the inner planets of our Solar System. Whether Kepler 22b actually contains water or life is currently unknown. A SETI project, however, will begin monitoring Kepler 22b for signs of intelligence.