Kepler telescope's planet-hunting days crunch to a close

"Kepler was my North, my South, my East and West, my working week, no weekend rest, my noon, my midnight, my talks, my song; I thought Kepler would last forever: I was wrong."

So laments planet hunter Geoff Marcy, with a due nod to W. H. Auden, upon hearing the news that NASA's Kepler space telescope is probably close to ending its search for extrasolar planets.

Since its launch in 2009, Kepler has discovered 132 exoplanets and identified nearly 3000 more possible planets, including a handful of potentially rocky worlds that may be able to host life. The mission's plethora of data has transformed our view of the galaxy, showing, for instance, that Earth-sized worlds should be common, and that one may even be lurking a mere 6.5 light years away.

But the pioneering telescope has been hobbled by a damaged reaction wheel, NASA announced at a press conference today. These wheels help Kepler keep its orientation in space, and precision steering is crucial to the mission.