'Invisible' world discovered: Planet alternately runs late and early in its orbit, tugged by second hidden world
Thursday, September 8, 2011 - 15:30
in Astronomy & Space
Usually, running five minutes late is a bad thing since you might lose your dinner reservation or miss out on tickets to the latest show. But when a planet runs five minutes late, astronomers get excited because it suggests that another world is nearby. NASA's Kepler spacecraft has spotted a planet that alternately runs late and early in its orbit because a second, "invisible" world is tugging on it.