Paranal: Foreseen Changes regarding Instrumentation and Facilities


The expected Paranal Instrumentation and Facilities to be offered in Period 112 and changes foreseen for Periods 113 and 114 are presented at the overview page.


  • Further improvements of the new Phase 1 system (p1) will take place in the following Periods.

UT instruments and facilities

  • MOONS - the Multi-Object Optical and Near-infrared Spectrograph – is expected to be installed at the UT1 Nasmyth A focus during the first or second quarter of 2024.
  • The VLT Visitor Focus at UT1 will be available, but the installation of the field corrector lens for MOONS may pose restrictions.
  • FORS1, the upgraded FORS instrument, is expected to be installed and see first commissioning in P113. FORS2 will thus be decommissioned in P114, and  first commissioning of FORS1 without the MXU is planned to occur in P114. Subsequent semesters will see the retrofit of the MXU to FORS1 together with subsequent commissioning.
  • ERIS - Additional modes and functionalities may be offered in P113, including the focal plane coroangraphy, L-band long-slit spectroscopy, rapid response mode, and pupil tracking for NIX imaging and IFS observations.
  • The recoating of the UT+VLTI coude train will continue with M5s and M7s. This activity will be performed one UT at a time, each time implying a two-month unavailability for VLTI+UT operations.
  • GRAVITY+ technical activities continue each period. In P113, the removal of the MACAO+DM adaptive optics on the four UTs and the installation of the GRAVITY+ AO modules will make the VLTI+UT unavailable for science operations for several months. In later periods, GRAVITY+ technical activities will take place until the installation and commissioning of Laser Guide Stars for VLTI (currently foreseen from 2025, P115).
  • In order to improve observability, functionality and baseline-complementarity between configurations, we plan to modify the definition of the standard AT medium configuration from K0-G2-D0-J3 (old medium) to A0-B5-D0-G1 (new medium) in a future period.