Chandra entered Normal Sun Mode (NSM) at 10:27pm EST on Feb 3 as the result of losing track of stars during an observation followed by a failure to re-acquire guide stars. The root cause was determined to be a recurrence of the ACA high background event which has caused entry into NSM once previously in the mission. Entry into NSM was nominal and assessment of the telemetry indicated that all spacecraft hardware was performing nominally. The recovery operations took place over Feb 4-5. Loads for a replanned schedule were uplinked on Feb 6 and science observations resumed on Feb 7 at 7:36am EST. Scheduled observations that were impacted by the anomaly and replan will be rescheduled in future weeks.

A real-time procedure was executed on Feb 5 to initiate a long ACIS CTI data collection while waiting to return to observing. Additional real-time procedures were executed on Feb 7 to perform a routine self-check of the Electrical Interface Assembly (EIA) Sequencer and to perform a diagnostic dump of the CPE.

Chandra passed through the 8th and 9th eclipses of the season on Feb 4 and 7 respectively, with nominal power and thermal performance.

A Chandra press release was issued on Feb 8 discussing new results regarding the black hole at the center of our galaxy, SgrA*. The new study suggests that Sgr A* is spinning very rapidly, which causes the spacetime around it to warp. To determine the spin of Sgr A*, the authors used an empirically based technique referred to as the “outflow method” that details the relationship between the spin of the black hole and its mass, the properties of the matter near the black hole, and the outflow properties. For details see: https://chandra.harvard.edu/press/24_releases/press_020824.html

The schedule of targets for the next week is shown below and includes an observation of SDSS J140701.59+190417.9 coordinated with HET.