NASA'S KEPLAR SPACECRAFT BROKE DOWN DUE TO TECHNICAL PROGRAM IN SPACE

Keplar spacecraft which was launched by Nasa in march, 2009 for the discovery of planets broke down due to a reaction wheel that control its pointing failed.
At last count, Kepler had discovered 3,548 possible planets, and 135 of them smaller than Earth have been validated by other observation, including earthbound telescope.
"The most exciting discoveries are going to come in the next few years as
scientist search through this data.
Kepler official mission was the fraction of the stars in the galaxy that harbor Earthlike planets by carrying out a survey of some 1,50,000 stars.
According to scientists, Kepler was designed to operate for four years, but other sunlike stars turned out to be more jittery in their output than expected, making the detection of Earth analogues more difficult. Since astronomers could learn a lot more from Kepler if it went on collecting data, the decision was made last year to extend the spacecraft's mission for three more years, until 2016. But due to break down this decision couldn't be possible.