23 May 2011 16:48

Spacecraft

The spacecraft continues to be in good health and is operating nominally.

Payload

Operations for all three instruments, PACS, SPIRE and HIFI, have been mostly nominal during the reporting period.

Both SPIRE and HIFI lost some observing time (2 days for SPIRE and a few hours for HIFI) due to a separate single event upset on each instrument. The affected observations have been rescheduled.

The 'PACS Unchopped Grating Scan Bright Line Mode' has been commissioned. The observing mode is available to the community for use in the second post-launch call for observing proposals, AO2, which is currently running (see below).

Ground Segment

Ground segment operations have been nominal and 100% of the data continues to be recovered. As of 12 May 2011, the approximate completion of the different programme parts was:

For more details of these different programme parts, see the "overview of Herschel observing" linked from the right-hand menu.

The second, and final, in-flight Announcement of Opportunity (AO2) process is ongoing. Like the previous AOs there are two parts to this final AO: a Call for Guaranteed Time Programmes (GT2) and a Call for Open Time Programmes (OT2).

The first part, the GT2 AO, was issued already on 7 April and closed during this reporting period, on 12 May 2011. A total of 32 proposals requesting 362 hours observing time in 441 observations were received by the submission deadline. The second part, the OT2 AO, will be issued next month, on 9 June, and will close on 15 September 2011.

After the conclusion of the evaluation process the approved proposals for both the GT2 and OT2 programmes will be announced in late November 2011. [Correction - 7 July 2011:  the GT2 programmes will be approved by end of May and the OT2 proposals will be approved in late November.] There will be no further AOs for Herschel observing time.

Mission Operations
During the reporting period, mission operations have been conducted with the support of ESA's New Norcia and Cebreros ground stations. Observational data stored on-board Herschel was received on ground during daily communication passes, each lasting approximately three hours.

Two tests were performed to establish the feasibility of using the Kourou ground station for Herschel communication passes. It was planned to use Kourou as alternative for the Cebreros ground station during a three week period in August 2011, when Cebreros undergoes maintenance. The tests showed that the Kourou station can not be used for Herschel operations: a significant fraction of the transmitted data was lost during the second test. The data were recovered from a backup station that had been provided for the duration of the test.

Archiving
The ground segment is operating nominally. Data products are generated routinely and ingested into the Herschel Science Archive (HSA).

As of 10 May the number of Herschel observations that are stored in the HSA has reached 27 000 (75 000 including older versions of observation products).

Future Milestones

• May 2011: Announcement of approved GT2 proposals.
• 25 May 2011: Third Direct Liquid Contents Measurement.
• 9 June 2011: Issuing date of the OT2 AO.
• 15 September 2011: Closing date of the OT2 AO.
• Late November 2011: Announcement of approved OT2 proposals.

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Legal disclaimer
This report is based on the Herschel mission manager's report dated 17 May 2011. Please see the copyright section of the legal disclaimer (linked from the home page http://sci.esa.int) for terms of use.