Well it seems the most Earth like planet is discovered circling a star 600 light years away....does it means life exist beyond Earth? A light year is the distance light travels in a year, about 6 trillion miles (10 trillion km). The planet called Kepler-22b is the smallest and the best positioned to have liquid water on its surface. It is 2.4 times the radius of Earth. Scientist are doing the follow up studies to determine if it is solid, like Earth, or more gaseous like Neptune.
A diagram comparing our own solar system to Kepler-22, a star system containing the first "habitable zone" planet discovered by NASA's Kepler mission released by NASA, Dec 5, 2011 - Reuters
