Solar telescopes GREGOR and VTT

Period 2020A (20 May – Aug)
Proposal Submission Deadline: 19 April 2020, 23 UT
Send proposals to

Proposals are hereby invited for observing time at the solar telescopes GREGOR and VTT at the Observatorio del Teide in Tenerife. This call is for observing time awarded under the SOLARNET Trans-National Access Programme.

This call is special in two ways:
– The COVID-19 situation implies that the time schedule for the observations is preliminary. It is likely that the observing period will be delayed until conditions allow it to start.
– GREGOR will be in a science verification phase following a redesign of its optical train that has improved image quality and performance. This means that special rules will apply regarding data rights and some other matters. See the information from the operator.

GREGOR Solar Telescope

GREGOR is a 1.5 meter on-axis solar telescope operated in PI visitor mode offering GRIS spectropolarimetry at wavelengths 1.0–1.3 or 1.5–1.8 microns. Operated in slit mode during science verification. GRIS observations can be complemented with fast context imaging in any wavelength below 900 nm if a suitable filter is available or provided by the observers.

VTT Solar Telescope

VTT is a coelostat with a 70 cm main mirror, operated in PI visitor mode, with three instrumentation options available.

  • The chromospheric or photospheric grating for spectroscopy in up to 3 spectral regions simultaneously.
  • Instrument setups provided by the user.

Proposal Submission

Time is typically awarded in blocks that are of the order of 10 days long. We expect that there will be about 10 d available on GREGOR and about 20 d on VTT.

Proposals requesting simultaneous use of GREGOR and VTT (co-observations) will be treated as one proposal to be accepted or rejected in its entirety. For the possibility of using only one telescope, please submit a separate proposal for that telescope.

For SOLARNET time, the PI and the majority of the users must be affiliated with institutions in EU (with the exception of Germany and Spain) or in associated countries or in the UK.

Proposals will be handled by the EAST TAC, a common European time allocation committee installed by the European Association for Solar Telescopes.

The proposal form and additional information on the instrumentation can be found here:

and on the adjacent “Scientific instruments” pages.

For technical questions, please contact Lucia Kleint (Email:

Data acquired in the SOLARNET Access Programme will become public one year after being delivered to the PI.