During the last week the observing schedule was replanned to increase the planning thermal margin for certain ACIS calibration observations during perigee. No science observations were impacted.

In detailed analysis of data for the Winter 2018 eclipse season, an anomaly was identified in the full charge current supplied by the Solar Array to Battery 3. During the eclipse on Dec 20, Chandra lost one of the five full charge Solar Array strings connected to Battery 3, resulting in a 20% reduction in full charge current. This level of current is sufficient for normal operations. The full charge current for Batteries 1 and 2 remains nominal, and the Solar Array power delivered directly to the spacecraft load bus was not impacted.

Chandra passed through the eighth (and final) eclipse of the season on Dec 30, with nominal thermal performance. The time required to recharge Battery 3 was longer than expected due to the Solar Array anomaly, but otherwise power performance was nominal.

Real-time procedures were executed on Dec 30 to disable SCS-29 and to dump and clear the EPS glitch counters as post-eclipse season actions. Another real-time procedure was executed on Jan 2 to perform a routine self-check of the Electrical Interface Assembly (EIA) Sequencer.

The schedule of targets for the next week is shown below and includes an observation of 3FGL J1544-1125 coordinated with HST.