Announcement of Opportunity (AO-2)

AO-2 Latest News - latest first, oldest last



  • Herschel lifetime assessment and AO OT2 time allocation. As part of the preparations for the AO OT2 time allocation process a reassessment of the predicted Herschel lifetime using all available information has been conducted. The conclusion is that the time period February/March 2013 is the most likely time for when Herschel will run out of helium, precluding any further observing (there is no "warm" Herschel mission).

    For the purpose of allocating OT2 priority 1 time a somewhat (but not very) conservative end-of-observing time of mid-February 2013 has been adopted. It has also been clarified that all pre-OT2 priority 1 observations (thus everything but OT1p2) if executed contiguously would last until mid-June 2012. Furthermore, Herschel has established a track record over long time of conducting 19 hours of science observations per day. Using this information, and redoing the calculation provided in Section 5.4.1 in the Policies and Procedures document, leads to 3420 hours (was 3300 hours) of OT2p1 time being available for allocation, all of which is intended and expected to be executed by Herschel.

    For OT2p2 time, using 3 months as a mission lifetime uncertainty (May 2013), and following the calculation in Section 5.4.2 in the Policies and Procedures document, leads to 4560 hours (was 3850 hours) of OT2p2 time being available for allocation. It can also be estimated that with the adopted mid-February 2013 lifetime about 18% of all priority 2 observations (OT1p2 plus OT2p2) will be executed, increasing with a longer actual lifetime.

    Late in the technical checking another proposal duplication was established. Thus, the final consolidated OT2 response is 530 proposals requesting a total of 12467.9 hours of observing time, which is a factor of 3.65 times the amount of OT2p1 time available as stated above.

  • Herschel AO OT2 response consolidated. The consolidated response to the AO OT2 is a total of 531 proposals requesting 12486.4 hours of Herschel observing time. Time request fractions in science areas and instrument use are similar to OT1. PACS is requested for slightly more than half the time, SPIRE and HIFI share the majority of the rest, plus some Parallel mode. Overall there are equal amounts of photometry and spectroscopy requested. The proposals are provided to the Herschel Time Allocation Committee (HOTAC) for scientific assessment.

  • Herschel AO OT2 proposal submission closed. The proposal submission deadline for the second in-flight Open Time (OT2) Announcement of Opportunity (AO) was on 15 September 2011. The preliminary outcome is a total of 531 proposals received, altogether requesting 12455.4 hours of observing time. These numbers are still TBC, and more detailed information will be posted after consolidation.

  • Special provisions applicable to OT1 priority 2 proposals and associated observations. We want to draw attention to Section 5.5 of the 'Policies & Procedures' document, associated to the current Announcement of Opportunity (AO-2) to apply for Herschel Open Time (OT2) proposals. Here the special provisions applicable to OT1 Priority 2 observing programmes and associated observations are provided and explained.

    It is important that you read them carefully. In particular it is emphasized that OT1 Priority 2 AORs are not blocked for other proposals (see Section 5.5 bullet 1).

    OT1 Priority 2 PIs have the possibility to re-submit (suitably updated if desired) proposals in this call (see Section 5.5 bullet 2).

    Shared proprietary rights are applicable to the observations included in these programmes in case they are duplicated by newly submitted OT2 Priority 1 proposals (see Section 5.5 bullet 3).

    We will be pleased to answer any question you may have on this matter through the HSC Helpdesk.

  • Plots representing the overall sky visibility by Herschel and the more demanded areas of the sky by Herschel users in previous calls. The plots below represent (left) the overall sky visibility by Herschel represented by a number between 0 and 1 which indicates the fraction of time in which a given area of the sky is visible to Herschel (1 means that the area is always observable by Herschel); and (right) the observation demand for different areas of the sky, as derived from the analysis of the observations approved in previous calls; this is represented in the plot as the ratios between the total number of hours requested in observations of a given area of the sky and the total time in which this area is observable by Herschel, normalised with respect to a mean value of 1.

    The brightest areas in this plot correspond to the Galactic Centre and Orion regions, which are almost simultaneously observable by Herschel. This may be useful information to consider when selecting the sample of targets to be observed under a given proposal, as selecting targets located in the least demanded areas of the sky may improve their chances of being scheduled. We emphasize, however, that the entire sky is available for proposing.


    Overall sky visibility by Herschel Relative Sky Pressure


  • Roll out of the Herschel Duplication Checker. The Herschel Duplication Checker (HDC), a duplication tool intended to help you in the preparation of your OT2 proposals while searching for duplications with observations included in the Reserved Observation List has just been rolled out.

    Please communicate any problem/question you may have while using this tool to the HSC Helpdesk by raising a ticket at the 'Reserved Observation List and Duplications' department.

  • Recent release of HSpot 6.0.1 A new version of HSpot (6.0.1) was released on 25 July to support OT2 Phase 1 proposal submission. HSpot 6.0.1 contains, among other things, a new version of the HIFI sequencer as well as a new functionality which allows the user to overlay the AORs included in the Reserved Observation List on any sky display generated by HSpot. For more details on this release you can read the note describing the main changes implemented in HSpot between v5.3 and 6.0 You should use HSpot 6.0.1 for your final OT2 proposal AORs.

  • Herschel lifetime and observing time available in the OT2 call. The amount of observing time available to offer in the OT2 call is discussed in Section 5.4 in the Policies and Procedures (P&P) document. Here end of February 2013 was assumed for helium boil-off to provide concrete numbers for illustration. Based on the results of the dedicated measurements performed at spacecraft level, and an analysis of the PACS and SPIRE internal cooler recyclings performed as part of Herschel observing, the current prediction for the running out of helium is the February-March 2013 timeframe. The assumption made in the P&P is thus in line with the best current lifetime estimate, and therefore the numbers presented for illustration in Section 5.4.3 are confirmed to be the most accurate numbers that can be provided at this point. The final assessment on how much time to allocate in OT2 will be performed at the time of the HOTAC meeting preparations, however, no dramatic changes are expected.

  • Herschel OT2 Announcement of Opportunity released! The second and final in-flight Open Time (OT2) Announcement of Opportunity (AO) process has started. The OT2 call has been released on 9 June 2011, with proposal submission deadline on 15 September 2011 at 12:00h UT. See the menu on the left.

  • HSC/NHSC Open Time Cycle-2 (OT2) Observation Planning Workshops to be held on 20-21 June 2011. For information about logistics and registration instructions, please visit the workshop websites:


  • The Guaranteed Time part (GT2) of the second (and final) in-flight Herschel Announcement of Opportunity has been closed on 12 May 2011. The preliminary outcome is a total of 32 proposals requesting 362.2 hours of observing time.

  • The Guaranteed Time part (GT2) of the second (and final) in-flight Herschel Announcement of Opportunity (AO-2) has been issued on 7 April 2011.