March 17, 2014
Scientists added a record 715 additional planets to the list of known worlds beyond the solar system, boosting the overall tally to nearly 1,700, astronomers said on Wednesday.
The additions include four planets about 2.5 times as big as Earth that are the right distance from their parent stars for liquid surface water, which is believed to be key for life.
The discoveries were made with the National Aeronautics and Space Administration’s planet-hunting Kepler space telescope before it was sidelined by a pointing system problem last year. The telescope, launched in 2009, spent four productive years staring at 160,000 target stars for signs of planets passing by, relative to the telescope’s line of sight.