Herschel Status Report - December 2011 and January 2012
06 Feb 2012 15:20
Report for period 21 November 2011 to 31 January 2012
Mission operations of the Herschel space observatory continued nominally during the reporting period, with the spacecraft and subsystems all performing as expected.
The spacecraft continues to be in good health and is operating nominally.
The improved knowledge of effects that contribute to the pointing accuracy of the Herschel observatory were discussed end November, to see how it can best be put to use. Herschel's absolute pointing error is confirmed to be reduced to about 1 arcsecond. As a result of this supreme pointing, as compared to the specifications, higher order effects can now be seen. Beyond feeding back the improved knowledge into the re-processing of already gathered data, two measures have been agreed to be implemented to improve the pointing for future observations:
After a long quiet period in autumn 2011, the instruments are again occasionally affected by single-event-upset induced bit flips in memory, sometimes leading to small losses in observing time. Apart from these few events, operations for all three instruments, PACS, SPIRE and HIFI, have been nominal during the reporting period. Indeed, the six-month average of executing observations still exceeds the pre-launch expectations, by more than 1 hour per day.
A large solar flare occurred on 23 January 2012 with a proton flux 40 times higher than the maximum observed by Herschel so far (see also "Solar flare - January 2012" in the right-hand menu). There is no damage to any of the three instruments. Possible degradations to the observations taken during this period were investigated. It was found that fortunately none of the observations taken during the Solar storm were affected to a degree that they would have to be repeated.
Ground segment operations have been nominal and 100% of the data continues to be recovered. As of 23 January 2012, the approximate completion of the different programme parts was:
For more details of the different programme parts, see the "overview of Herschel observing" linked from the right-hand menu.
The second, and final, in-flight Call for Open Time Proposals (OT2) for observing with Herschel was closed in mid-September 2011. Well over 500 proposals had been received and were reviewed by the Herschel Observing Time Allocation Committee. The committee's recommendations have now been endorsed and communicated to the proposers. Over 370 proposals have been accepted. The scheduling of priority 1 observations from these OT2 programmes has started.