ESO may schedule observing programmes in Designated Visitor Mode (dVM) rather than regular Visitor Mode (VM). This is the default mode for observing runs shorter than one night and may also be offered for longer programmes to reduce travel requirements and environmental impact.

In Designated Visitor Mode, observations are scheduled in dedicated observing slots in the same way as Visitor Mode observations. However, the observations are executed on site by ESO staff in close coordination with the Principal Investigator (PI), or a designated representative acting as the liaison with the Observatory.

During the observations, observers can follow the execution remotely via a Microsoft Teams connection. Screen sharing allows monitoring of target acquisition and instrument status, while operational control remains with ESO staff.

Before your run

Getting ready

Your ESO User Portal account provides access to the observing run webletters containing information specific to your programme. The same credentials are used to access p2, the web-based application for preparing observations.

For general information on observation preparation, please consult the Phase 2 page.

We encourage you to familiarize yourself with the instrument(s) you will be using. Instrument-specific documentation can be accessed through the instrument pages listed in the navigation menu. Many instruments also provide dedicated guidance and recommendations for visiting astronomers.

Preparation of observing material

All observations must be prepared using p2. 

All observing material must be prepared and submitted at least 10 days before the first scheduled observing night. The required material includes:

• A README file with contact information for observers [First+Last name and email (mandatory), phone number (optional). Details of non-standard instrument configurations or calibration requirements.
• Prepare all required Observing Blocks (OBs). OBs should contain finding charts (and ephemeris file for moving target observations for the scheduled nights).

Once the preliminary observing material is ready, please use the "Notify ESO" function in p2 to inform the Observatory. If the required observing material is not submitted by the deadline, ESO may convert the programme to Service Mode.

To maximize the scientific return of your observing run, you can prepare additional targets that can be observed if observing conditions are better than anticipated and backup targets that can be observed if weather conditions prevent execution of your primary programme. Please note that strong winds at Paranal often originate from the north; therefore, southern backup targets are particularly useful. Requests for additional targets, backup targets, or changes to instrument configurations must be submitted and approved well in advance according to this procedure.

Questions and support

Questions regarding observing material preparation should be submitted through the Deskpro ticket associated with the run.

During the observations

Initial Contact

Unless prior discussion is required, the first operational contact between the observer and the Observatory typically takes place during a Teams meeting at sunset on the first observing night. During this meeting:

• The observing material and OBs are reviewed.
• The observing strategy is discussed.
• Any final questions can be addressed before execution begins.

Observers may be able to use part of evening and morning twilight for observations unless required for observatory activities. 

Remote Monitoring

During the observing run, observers can:

• Follow target acquisition and observation execution through screen sharing in the Teams meeting.
• Monitor instrument status and operational activities.
• Communicate directly with the ESO staff conducting the observations.

Operational control of the telescope and instruments remains with ESO personnel at all times.

Current atmospheric and weather conditions can be monitored using the Astronomical Site Monitor (ASM).

(As a backup solution, a web-based remote viewing facility called POEM and following the online instructions is still available.)

After your run

Data access

Data are made available through the ESO Science Archive shortly after acquisition and can be accessed via the ESO User Portal.

The CalSelector service can be used to automatically retrieve all associated calibration files required for data reduction.

Observers will also receive a copy of the electronic night report by email.

Data quality information

Data quality information is communicated during the observations by the telescope operator and observatory staff.

Raw data can be downloaded directly from the archive, and quick-look products or selected pipeline-reduced data products are available when applicable.

End-of-mission report

Feedback from observers is an important part of improving observatory operations and user support.

Following the observing run, observers will receive an invitation to complete an online feedback survey. We greatly appreciate your participation.

No compensation for weather or technical downtime

As a general rule, the observatory does not compensate Designated Visitor Mode programmes for time lost due to adverse weather conditions or technical problems.

In exceptional circumstances involving a near-total loss of observing time (typically more than two-thirds of the allocated programme time) caused by technical issues, compensation may be considered by the Director on a case-by-case basis.