The new "first light" images show the mission's target patch of sky, a vast starry field in the Cygnus-Lyra region of our Milky Way galaxy. One image shows millions of stars in Kepler's full field of view, while two others zoom in on portions of the larger region. One new image from Kepler shows its entire field of view — a 100-square-degree portion of the sky, equivalent to two side-by-side dips of the Big Dipper. The regions contain an estimated 14 millions stars, more than 100,000 of which were selected as ideal candidates for planet hunting. Two other views focus on just one-thousandth of the full field of view. In one image, a cluster of stars located about 13,000 light-years from Earth, called NGC 6791, can be seen in the lower left corner. The other image zooms in on a region containing a star, called Tres-2, with a known Jupiter-like planet orbiting every 2.5 days.
Kepler will spend the next three-and-a-half years searching more than 100,000 pre-selected stars for signs of planets. It is expected to find a variety of worlds, from large, gaseous ones, to rocky ones as small as Earth. The mission is the first with the ability to find planets like ours -- small, rocky planets orbiting sun-like stars in the habitable zone, where temperatures are right for possible lakes and oceans of water. To find the planets, Kepler will stare at one large expanse of sky for the duration of its lifetime, looking for periodic dips in starlight that occur as planets circle in front of their stars and partially block the light. Its 95-megapixel camera, the largest ever launched into space, can detect tiny changes in a star's brightness of only 20 parts per million. Images from the camera are intentionally blurred to minimize the number of bright stars that saturate the detectors. While some of the slightly saturated stars are candidates for planet searches, heavily saturated stars are not. Scientists and engineers will spend the next few weeks calibrating Kepler's science instrument, the photometer, and adjusting the telescope's alignment to achieve the best focus. Once these steps are complete, the planet hunt will begin.