A Spanish Scientific and Technical Infrastructure

40m RT call for proposals

Standard Call

Due to the aftermath of the intense snowstorm Filomena back in January, which critically affected systems vital to observations with the Yebes 40m radiotelescope, we have been unable to complete projects accepted for the 2021A semester. We thus regret to inform that there will be no Call for Proposals for semester 2021B. Instead, proposals awarded with telescope time in semester 2021A will be observed during the second semester of the year, and the resulting data subsequently sent to the IPs. We apologise for any inconvenience this might cause.

We recall that Director's Discretionary Time (DDT) is still available and can be applied for at any time through RAYO, should you have any urgent, target of oportunity or groundbreaking projects (see below).

The 40 m radiotelescope is operated by the Observatory of Yebes, Instituto Geográfico Nacional. It is equipped with receivers at different frequency bands between 2 and 90 GHz. For more information on the telescope please refer to the 40m RT page.

Director's Discretionary Time (DDT)

Since 2019, a small fraction of the observing time is open, through the whole year, to proposals classified as Director's Discretionary Time (DDT). Under this type we consider:

  • Target-of-Oportunity (ToO) proposals for sources which show transients.
  • Urgent proposals which require immediate observations due to their high impact or highly competitive goals that lead to exceptional results or continuation observations of recent discoveries that need to be complemented.
  • Proposals that want to test new ideas which are potentially disruptive and which can be performed in a short time.


Apart from filling the application form, it is mandatory to include a scientific and technical justification that must be uploaded as a separate PDF file. The maximum extension of regular proposals is 4 pages in A4 format including references, figures and tables. DDT proposals have a maximum extension of 2 pages. A simple LaTeX template is provided here for such purpose.

Any questions regarding the submission process should be addressed to m.santander at

Pablo de Vicente.
Director of the Observatory of Yebes, Centro de Desarrollos Tecnológicos