During the last week the observing schedule was interrupted by a high-radiation event that activated the science instrument safing sequence (SCS 107) and stopped observing at 10:18pm EDT on May 16. All spacecraft actions were nominal. An observation of Sgr A* was impacted and the time lost will be rescheduled. Real-time procedures were executed on May 17 to disable SCS-29 (which was enabled during the safing sequence), to verify that the radiation environment as observed by the HRC anticoincidence shield had decreased to an acceptable level, and to start a collection of ACIS CCD charge-transfer inefficiency data. Loads for a replanned schedule were uplinked on May 18 with 93.8ks of science loss.

A real-time procedure was executed on May 16 to re-initialize the flight software Thruster Command Processing subfunction in order to prevent the occurrence of an overflow condition.

A Chandra image release was issued on May 15 describing the results of observations of the supernova SN 2010jl. SN 2010jl was first spotted by astronomers on November 3, 2010, and probably exploded about a month before that. These observations provide the first evidence in X-rays of a supernova shock wave breaking through a cocoon of gas around the star. This discovery may help explain why some supernova explosions are more powerful than others. For details see: http://chandra.si.edu/photo/2012/sn2010/

The schedule of targets for the next week is shown below and includes an observation of MAXIJ 0556-332, which was accepted as a Target of Opportunity on May 8.