La Silla Paranal Period 117 Time Allocation

Published: 02 Feb 2026
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The time allocation process for ESO telescopes for Period 117 has been completed. This was based on the scientific evaluation of the Distributed Peer Review (DPR) and the Observing Programmes Committee (OPC), who met in November 2025 to provide recommendations to the ESO Director General. A total of 13070 hours of (Designated) Visitor Mode and Service Mode observations (excluding filler programmes) were allocated on the VLT/VLTI, the 3.6-metre, and NTT telescopes.

Large Programmes and KMOS Public Surveys on the VLT occupy 32.5% of the allocation. The Guaranteed Time Observations and Large Programmes on the 3.6m amount to 45.8%. The VLT Unit Telescope with the highest effective pressure* was UT1 (11.5), due to ongoing KMOS Public Surveys and planned MOONS commissioning, followed by UT4 (9.0). ESPRESSO-1UT observations were distributed between UT2 (6.7) and UT3 (8.3). VLTI-UT had three times higher demand than in the past, which resulted in allocating on average over 9 nights per month for VLTI-UT observations and the effective pressure on VLTI-UT was of 8.6. On the VLT, the balance between Visitor and Service Mode in Period 115 is about 15/85, excluding filler programmes. The schedule for VLT/VLTI includes a provision for up to 15% of the time for a future Fast Track Channel Call for Proposals. 

The schedule timeline and the list of scheduled runs is publicly available. The ESO Observatory Statistics webpage provides further telescopes statistics. The outcome of the time allocation was communicated to the Principal Investigators of proposals submitted for Period 117 on Monday, 2 February 2026 and can be accessed directly in the P1 tool. Users are kindly asked to provide feedback on the quality of the evaluation of their proposals by the OPC Expert Panels or DPR in P1, thereby helping us to monitor the quality and effectiveness of the proposal review process.

Effective pressure is the one experienced by normal programmes, i.e. once one has removed all the technical/commissioning activities, the pre-committed LPs/Monitoring, the new LPs and the GTO.