NASA to Attempt Fix for Planet-Hunting Kepler Spacecraft This Month

NASA will try to revive its ailing Kepler spacecraft this month in the hope of resurrecting a mission that has revolutionized the search for alien planets.

 Launched in March 2009, NASA's Kepler space telescope has detected more than 3,000 potential alien planets. But that exoplanet hunt stalled in mid-May of this year, when the second of Kepler's four orientation-maintaining reaction wheels failed, hobbling the spacecraft.

Since then, the Kepler team has been working on possible fixes for the reaction wheels and plans to try them out out in the coming weeks, officials said.

"The engineering team has devised initial tests for the recovery attempt and is checking them on the spacecraft test bed at the Ball Aerospace facility in Boulder, Colo.," Kepler mission manager Roger Hunter, of NASA's Ames Research Center in Moffett Field, Calif., wrote in an update Wednesday (July 3).

"The team anticipates that exploratory commanding of Kepler’s reaction wheels will commence mid-to-late July."

Kepler spots exoplanets by noting the telltale brightness dips caused when they cross their parent stars' faces from the instrument's perspective.

This is precision work, and the observatory needs three functioning gyroscope-like reaction wheels to stay locked onto its 150,000-plus target stars.

Kepler launched with four reaction wheels, with one set aside as a spare. One wheel, known as number two, failed in July 2012.

Number four then bit the dust on May 11 of this year, bringing the spacecraft's planet-hunting work to a halt.