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 10:41pm EDT on Sep 6. All spacecraft actions were nominal. Real-time procedures were executed on Sep 7 to disable SCS-29, which was enabled during the safing sequence, and to update the observation identifier number, to aid CXCDS processing of the interrupted observation. Observations of M30 and the Chandra Deep Wide Survey were impacted by the interruption. Lost time will be rescheduled.

A real-time procedure was executed on Sep 5 to perform an annual check-out of A-side MUPS thrusters, which are selected for use when Chandra is in its safe-mode configuration. Thrusters A2, A3, and A4 were fired. Thrusters performed nominally. Thruster A1 was not fired due to the expected limited life remaining on it. Another real-time procedure was executed on Sep 7 to perform a routine self-check of the Electrical Interface Assembly (EIA) Sequencer.

A Chandra press release was issued on Sep 6 describing observations which reveal that stars like the Sun and their less massive cousins lower their activity levels surprisingly quickly after an active youth. This result has positive implications for the long-term habitability of planets orbiting such stars. For details see: http://chandra.si.edu/press/17_releases/press_090617.html,/p>

The schedule of targets for the next week is shown below and includes four observations of NGC1313 X-1 coordinated with NuSTAR, and an observation of SN2017egm, which is a follow-up to a Target of Opportunity which was accepted on Jun 17.