Extrasolar planets coming into focus
The discovery of a planet orbiting a dim dwarf star about 20 light-years from Earth has encouraged astronomers in their hunt for habitable, and maybe even inhabited, worlds elsewhere in the galaxy (SN: 10/23/10, p. 5). Though some researchers question the finding (SN: 11/6/10, p. 14), astronomers suspect that dozens of potentially habitable worlds will be discovered as the number of known exoplanets continues to climb.
The Kepler spacecraft, which monitors some 156,000 stars for dips in starlight that indicate the passage of planets, had found a whopping 706 candidate bodies by June, bringing the total of presumed extrasolar worlds to well over 1,000. One of Kepler’s discoveries, though much too close to its parent star to support life, has a diameter only about twice that of Earth (