Earth-like planets may be closer than thought: study

Scientists looking for habitable planets may not have to stray far from our galactic neighborhood, said a new study Wednesday, which calculated an Earth-size planet could be orbiting a red dwarf as near as 13 light years away.

“We thought we would have to search vast distances to find an Earth-like planet. Now we realize another Earth is probably in our own backyard, waiting to be spotted,” said Harvard astronomer and lead author Courtney Dressing.

The researchers based their calculations on planets already discovered by the US super-telescope Kepler, focusing on the question of which “red dwarf” stars could have potentially habitable Earth-size planets in their orbits.

Red dwarfs are smaller, cooler and fainter than our solar system’s sun — and they are also the most commonly found stars in our galaxy, making up about three of every four stars in the Milky Way.

Kepler casts its gaze on around 158,000 stars and, based on the analysis by Dressing and her team, the telescope has identified 95 planetary candidates orbiting red dwarf stars.

But most of those planets weren’t quite the right size or temperature to support life, so the researchers narrowed the candidates to just three that were both warm and approximately Earth-sized.

Projecting outward based on the estimated 75 billion red dwarf stars in our galaxy, they arrived at the prediction that around six percent of red dwarfs should have an Earth-like planet, and the nearest one could be just 13 light years away.

more here: http://www.rawstory.com/rs/2013/02/06/earth-like-planets-may-be-closer-than-thought-study/