Sun's stroke keeps Kepler online, Nature
"Wiemer had fashioned a crutch for Kepler using the only resource available: sunlight. Positioned so that its long side faces the Sun, the spacecraft leans against the pressure created by the onslaught of photons and balances using its two good wheels. With this approach, the team hoped to get within a factor of ten of Kepler's original performance -- but with additional software refinements, NASA's Kepler project manager Charlie Sobeck says that it is better than that, more like a factor of two or three. Wiemer thinks that further tweaks will close the gap entirely. One limitation of the K2 mission is that Kepler must keep the Sun side-on as it orbits, forcing the telescope to switch its field of view roughly every 80 days. This is not enough time to hunt for Earth-like planets around Sun-like stars, but it does let K2 track other celestial bodies such as clusters of newly-formed stars."