Kepler mission maybe over for good..

Tests have failed to restore the Kepler space telescope's ability to aim precisely at distant stars, but NASA hopes to find an alternative mission for the planet-hunting probe, the space agency announced Thursday.

Kepler has been sidelined since mid-May, after the second of four devices used to aim the spacecraft's telescope gave out. Controllers have been trying to restart at least one of those two devices, known as reaction wheels, but both are generating too much friction to keep operating, NASA officials said.

The roughly $600 million mission has so far confirmed 134 planets and identified nearly 3,300 possible planets beyond our solar system.

NASA is now looking to determine whether there are other observations Kepler can make that don't require the kind of precise control needed for its original role -- "and whether that science is compelling enough to justify continued investment in Kepler operations," said Paul Hertz, the head of NASA's astrophysics division.