Paranal Science Operations

General Information

Paranal Science Operations (PSO) is the department of the La Silla Paranal Observatory that is in charge of the operation of the telescopes on Paranal. These telescopes are:

  • The four Unit Telescopes (UTs) forming the VLT.
  • The VLTI, which is the interferometric combination of either the UTs or the Auxiliary Telescopes (ATs).
  • The VST and VISTA survey telescopes.
  • And in the future: the ELT!

Watch live webcam pictures from the summit of Paranal. For real-time information of the atmospheric conditions on site, see the ASM.

If you are interested in working at Paranal, you are invited to inform yourself about the career prospects and working conditions in the PSO department. Also check out our alumni page to see where our previous department members are working now.


PSO News

  • March 29, 2022: La Sila Paranal Observatory is back to full operations. Visitor mode on site is offered as of June 2022. 
  • November 23, 2021: PSO operates close to pre-pandemic levels. Visitor mode is still executed in designated mode dVM.
  • November 6, 2021: Users of designated visitor mode programs can view from their computer at home the relevant operation panel in the Paranal control room, via the Paranal Observatory Eavesdropping Mode (POEM). Access credentials will be provided by the mountain staff at the beginning of the run. Up to 5 users can connect to 1 terminal, 1 user can connect up to 5 terminals (if the need arises to monitor more than 1 terminal).
  • POEM is also available for co-Is that want to join visiting astronomers on the mountain remotely.September 18, 2020: First scientific data taken with UVES@UT1 and FORS@UT2. Please see the LPO news page for up-to-date information on the systems back in operations.
  • August 28, 2020: Minimal science operations to be resumed at Paranal, foreseen starting date September 23. Please see the LPO news page for more details.  . 
  • March 24, 2020: Science operations at Paranal have been stopped due to the Covid pandemic. For regularly updated news given the Corona virus situation, please consult the LPO news page.


Information for Observers

In the SciOps pages, you should find all the information you need for your observations from the time you have an idea of observations until when you finish processing your data. The menu on the left contains the list of the PSO pages for the astronomers, which are described in more details hereafter. Also, some useful ESO pages (not belonging to PSO) can be accessible from the left sub-menus.

  • Preparing your proposals for observing time and your observations

  • Visiting astronomer coming to Paranal

    • Before your observation run: familiarize yourself with the technical documentation and with p2
    • This Visitor Information page contains the info you will need. 
  • Designated Visitor Mode Observations (dVM)

    • Although the preparation and execution of your dVM run are similar to that of a VM run, the preparation of the observing material should follow the phase2 guidelines.
    • At least 10 days before your run, please have your observation material prepared within p2, including the Readme file. 
    • This Designated Visitor Information page contains the info you will need.
  • Service Observation

  • After the observations...

    • Observer feedback is very important for the Observatory and we would appreciate if you could take the time to fill our web-based survey (a link will be send via email after your run).
    • Pipelines and Quality Control pages
    • Science Archive
  • Special cases - Targets of Opportunity and Director Discretionary time:

    • DDT Instructions: how to apply for Director Discretionary time.
    • RRM trigger instructions for triggering Rapid Response Mode Observations.
    • RRM Status: log of the instrument status and of the RRM triggers.
    • ToO Policies: the rules governing the execution of ToO at the La Silla Paranal Observatory.
  • Other policies


Technical Information