Observing at the VTT

View of ChroTel from the 2nd floor of the VTT right after a blizzard in Feb. 2014

Observing Season:

The VTT observing season typically starts in April and ends at the beginning of November (for obvious reasons - see picture).


Note: Due to the rapidly changing situation with the corona virus, it is unclear when we can start operating. Nevertheless, we carry out the call for proposals anyway to be ready when the restrictions are lifted. The dates below might therefore change.


VTT has two observing seasons in 2020 with 140 observing days: May 1 - October.


VTT/GREGOR – Call for Observing Proposals 2020A (May 1 – beginning of August)

We invite proposals for observing campaigns at VTT in 2020A, with a submission deadline of April 19, 2020, 23 UT.


The available instrumentation is:

•    The chromospheric or standard grating for spectroscopy in up to 3 spectral regions simultaneously

•    Own instrument setups

•    Hellride


Requests for technical time should be accompanied by a daily schedule of the planned work.



Apply for observing time:

The VTT is open to external users. The observing time at the VTT has various quotas. All user groups are invited to apply for observing campaigns via one of the following TACs. Please use the observing proposal available for download on the bottom right of this website.


The different quotas for VTT observing time in 2020A are:
- KIS: 25 days. Eligibility: Any researcher with no restriction on institute/nationality can apply for observing time if at least one collaborator from KIS is included in the proposal.

- Spanish time: 14 days. Application via Spanish CAT. Eligibility: No restriction on institute/nationality.
- CCI time: 7 days. Application via EAST TAC. Eligibility: Anybody apart from the operators of the telescope.
- SOLARNET (Send proposals to east-tac@astro.su.se): 20 days. Eligibility: The PI and the majority of the users must work at institutions which are outside the country(ies), which operate the telescope (Germany, Spain). This means the PI and 1/2 of the CoIs have to be from the EU, associated states, or the UK, except for Spain and Germany. Travel and lodging grants are available for up to 2 people.
 Joint applications for GREGOR+VTT wil be approved or rejected as a whole, so please consider whether you apply for joint observations, or for a single telescope.



Spanish time (CAT Solar)

Contact Solar Cat at IAC for more information.

German time (split between the AIPMPS, and KIS)

Contact tac@leibniz-kis.de for more information.


In 2020A, 20 days are available at VTT. Send proposals to east-tac@astro.su.se.


A common observing time allocation process for European Solar Telescopes was one of the achievements of the trans-national ACCESS program of OPTICON (FP7). This European Time Allocation Committee was established by EAST. The EAST TAC provides a common standard of review for all observing proposals. Observing time quotas for all European telescopes and instruments can be allocated by the EAST TAC. The EAST TAC allocates SOLARNET ACCESS time and CCI international time. SOLARNET is the solar successor of OPTICON, and started in April 2013. Main objectives are to provide access to European Solar telescopes and instruments, and to develop data pipelines such that science-ready data is easily available for users of the ACCESS program.


Observing Proposals

External and new users are explicitly encouraged to apply for observing time through one of the above programs. Please contact Lucia Kleint (lucia.kleint@kis) if you are interested in observing at the VTT or if you need help. 

Proposal forms 2020 are available in the right column.

Deadlines for applications to the 2020 observing season are: