Reporting period: November 2021 – October 2022
The Chandra X-ray Observatory has carried out more than 23 years of highly successful and productive science operations. Chandra is unique in its capability to produce the sub-arcsecond X-ray images that are essential for accomplishing the science goals of many key X-ray and multi-wavelength investigations in current astrophysical research. The Project is looking forward to many more years of scientific productivity.
In recognition of the superb performance by the Chandra X-ray Center’s staff in operating Chandra and serving the scientific community and of Chandras continuing contributions to astrophysical knowledge, the 2022 NASA Senior Review panel rated the Chandra program Excellent, its highest rating.
The High Resolution Camera (HRC) is in the process of being returned to normal science operations following hardware anomalies in August 2020 and February 2022. Chandra is equipped with duplicate sets of electronics and hardware for many functions, and HRC had been operating for over a year on its backup circuits. After careful analysis and review, staff returned HRC functions to its primary set of control electronics. HRC has recently successfully carried out several science observations as part of a testing program prior to return to regular operations.
The Observatory continues to operate extremely well overall, but with a number of incremental changes in performance. The gradual accumulation of molecular contamination on the UV filter that protects the ACIS detector reduces ACISs sensitivity to low-energy X-rays. Overall spacecraft heating due to the slow degradation of Chandras multi-layer thermal insulation requires extra effort in scheduling observations. Nevertheless, the CXCs mission planning teams have successfully maintained Chandras observing efficiency at ~70%, the maximum available as determined by the need to protect the Observatory’s instruments as Chandra passes through Earth’s radiation belts.
In response to the December 2021 call for proposals for Cycle 24 observations, scientists worldwide submitted 423 proposals, including 357 proposals for observing and 66 for archive and theory research. Observing proposals requested 73.3 Ms of telescope time, for an oversubscription factor of 4.0. In June the Chandra Directors Office conducted the annual peer review of proposals via remote access. The review approved 136 observing proposals and 18 archive and theory proposals for a total of 18.4 Ms of observing time.
This summer, the CXC held a workshop, Supernova Remnants and Their Progenitors, during August 16-18, 2022. The workshop, which was conducted both in-person and via remote access, featured 9 invited speakers.
The Chandra Press Office has been active in issuing image releases, science press releases, and other communications of Chandra research results. A complete listing is available at http://chandra.harvard.edu/press. Information about the Chandra Observatory and the Chandra X-ray Center can be found at http://cxc.harvard.edu/.