Damaged Kepler space telescope may find new use

New Scientist : Although the Kepler space telescope has been hobbled by the failure of two of its four reaction wheels , which help stabilize the craft in space, two researchers propose modifying its mission so that the telescope could continue to produce useful data. Since its launch in 2009, Kepler has discovered 132 exoplanets and more than 3000 other possible ones. Now Keith Horne of the University of St. Andrews in the UK and Andrew Gould of the Ohio State University propose that Kepler could alter its search: Instead of looking for planets inside a solar system’s snow lineâmdash;close enough to their stars that liquid water could existâmdash;it could use microlensing to search for worlds outside the snow line. The study of both extremes is necessary to help scientists better understand the so-called habitable zone where extraterrestrial life may one day be found. Although Earth-based telescopes can also use microlensing, Kepler, whose orbit trails Earth’s, can see things that can’t be seen from the ground.