Kepler Mission Manager Update
Kepler is more than 10,700,000 kilometers (about 6,600,00 miles) from Earth and continues its planned drift-away orbit. Since May 12, 2009, Kepler has been observing its target region near the Cygnus constellation. Today, data collected continuously since science operations began on May 12, 2009 were downloaded to the Kepler Science Operations Center at Ames Research Center, Moffett Field, Calif. The data were collected from observing over 145,000 stars simultaneously. Scientists will begin in earnest the analysis of this data to search for other Earth-size planets. Engineers also completed Kepler's planned quarterly roll. This roll will ensure that Kepler's solar arrays are kept optimally positioned with respect to our sun, to ensure proper power generation, for the next three months. Both the science data download, and the quarterly roll, are Kepler "firsts" in its planned three-and-a-half-year mission.
On June 15, 2009, Kepler entered safe mode, a protocol executed by the spacecraft as a precautionary safety feature. In this case, the safe mode entry was caused by a fault in part of the spacecraft processor. Upon detection of the entry into safe mode, engineers began anomaly response procedures to determine spacecraft health and status, cause of the fault, and recovery. Engineers determined the spacecraft's stored science data was safe. The fault caused the Kepler photometer to turn off. Further analysis indicated the Kepler subsystems were not endangered by the fault. Engineers re-initialized the photometer, downlinked the science data, performed the quarterly roll, and returned the spacecraft to its mission. Analysis will continue on spacecraft telemetry files to better understand the root cause of the safe-mode event. The mission baseline allows for 12 days per year for potential safe-mode events such as this one. This particular event consumed about one-and-a-half days of what would have been time collecting science data. In mission dress rehearsals prior to launch, the Kepler team practiced responses to non-nominal conditions, like safe-mode events and spacecraft malfunctions. Thanks to this practice, the team responded effectively and efficiently to restore Kepler to its nominal operational status. Twice-per-week routine contacts with the Kepler spacecraft will resume, as Kepler collects another 30 days of science data in its hunt for Earth-like planets. The next science data download will occur in late July.