During the last week Chandra completed the observing schedule as planned.

Chandra passed through the seventeenth, eighteenth, and nineteenth (and final) eclipses of the season on Dec 11, Dec 13, and Dec 16 respectively, with nominal power and thermal performance. Real-time procedures were executed on Dec 16 to disable SCS-29 and to dump and clear the EPS glitch counters as post-eclipse season actions.

Of note this week was the release on Dec 15 of the Cycle 24 Call for Proposals. The proposal submission deadline is 10 March 2022. In conjunction with the call was the release on Dec 14 of the CIAO 4.14 analysis software system and DS9 8.3. For details see:
https://cxc.cfa.harvard.edu/proposer/
https://cxc.cfa.harvard.edu/ciao/download/
and
https://ds9.si.edu/site/Download.html

Chandra press and image releases were issued on Dec 16 describing a new Chandra study of the galaxy cluster known as RBS 797, located about 3.9 billion light-years from Earth. The study disclosed two separate pairs of cavities extending away from the center of the cluster. Such cavities are common in the hot X-ray emitting gas that fills the space between galaxies in clusters, and are believed to originate in eruptions from supermassive black holes in central cluster galaxies. The remarkable feature of the RBS 797 cavities is that there are two sets directed perpendicular to each other. The presence of two active black holes in a mutual orbit is the basis of one explanation of this structure. Another explanation is based on a single black hole that shifted the direction of its jets within about 10 million years, a remarkably short time. For details, see https://chandra.harvard.edu/press/21_releases/press_121621.html

The schedule of targets for the next week is shown below and includes an observation of LHS2021 coordinated with HST.