by Jim Fanson, Kepler, JPL Project Manager
Kepler Mission Manager Update
The Kepler telescope's focus has been successfully optimized. This involved moving the primary mirror of the telescope toward the focal plane array, the area where light is focused, by 40 microns (1.6 thousandths of an inch) and tilting it by 0.0072 degrees. Various other calibrations are underway, including: detailed measurement of star images formed by the telescope at various locations on the focal plane; determination of the exact sky coordinates of every one of the camera's 95 million pixels, and mapping of "ghost" images, which result when the light from bright stars reflects off the front of the camera's charge-coupled devices (CCDs), bounces off lenses inside the telescope, and winds up back on the CCDs in another location.