TARSIS: construction starts for the future instrument of the largest Calar Alto telescope.


Telescopio 3.5m en CAHA

TARSIS will be the next instrument to be installed on the 3.5-meter telescope at Calar Alto observatory. It is an integral field spectrograph with unique characteristics, capable of observing very wide fields in the near ultraviolet. TARSIS will make it possible to complete CATARSIS, a large survey of galaxy clusters, keeping Calar Alto at the forefront of astrophysical research.

On October 27-28th, 2022, the TARSIS kick-off meeting will take place at the University of Almería, marking the start of the development of the TARSIS instrument for the 3.5-meter telescope at Calar Alto observatory. This project is co-led by the Institute of Astrophysics of Andalusia (IAA-CSIC) and the Universidad Complutense de Madrid (UCM), in close collaboration with the Calar Alto Observatory (Hispanic Astronomical Center in Andalusia, CAHA), three Andalusian universities (Almería, Granada and Seville), the Astrobiology Center (CAB, CSIC-INTA), the industrial partner FRACTAL S.L.N.E. and the Mexican INAOE.

The kick-off event will be a meeting point for all the team members who will participate in the development of TARSIS, as well as a starting point for the design of the different subsystems that will make up the instrument once its development is complete. In addition, a visit to Calar Alto is planned so that the entire project team can see where the fruit of their work will stand.

TARSIS is an integral field spectrograph, based on a large image slicer which allows to obtain a spectrum for each narrow band of the pointed celestial field, giving complete information about the object being observed. The name TARSIS, an acronym for Tetra-ARmed Super-Ifu Spectrograph, refers to its optical design based on four arms: three of them sensitive to blue wavelengths and one sensitive to red wavelengths. The combination of a wide field of view (3x3 arcminutes) and high sensitivity from ultraviolet (in the range known as UV-A rays) to red wavelengths will make TARSIS a unique instrument. The design of TARSIS and the exquisite transparency of Calar Alto's sky will permit observations in the full UV-A range, a domain almost unexplored from Earth.

 instrument tarsis  Tarsis Instrument

"Only the unique features of TARSIS allow us to fully map galaxy clusters at distances where we can still resolve the internal structure of galaxies over a wide range of energies," says Jorge Iglesias, TARSIS Co-Principal Investigator at IAA-CSIC. Armando Gil de Paz, co-principal investigator of the project at UCM, adds that "TARSIS is a great challenge, since obtaining information in such a wide energy range and in a field of this size in two-dimensional spectroscopy is unprecedented in any ground- or space-based telescope. This way, while classical spectroscopy barely covers a narrow slice of the sky, TARSIS will observe 160 of them."

Once the development is completed, TARSIS will become part of the instrumentation available for the Calar Alto 3.5-metre telescope. According to Jesús Aceituno, director of CAHA “Astronomical observatories have to constantly adapt and renew themselves in order to remain at the forefront of modern astrophysics. TARSIS will bring this opportunity to Calar Alto, because once again, we will have a unique instrument in the world to do science that has not been done to date.

During the first years of observations, TARSIS will be largely devoted to the CATARSIS project, which will study a sample of sixteen distant galaxy clusters to better understand the earlier stages of the universe: these are galaxies between 20% and 25% less massive than the present ones but which, on their way to become the galaxies we see today, were forming stars at three times the present rate. The CATARSIS observations will make it possible to validate the standard cosmological model and understand the nature of dark matter and dark energy, as well as the relationship between the evolution of galaxies and their environment.

The construction of TARSIS will be financed through European regional development funds (ERDF) and contributions from the institutions of the consortium in the form of facilities and personnel. The total cost of the instrument is estimated at 7.8 million euros, of which the Spanish Ministry of Science and Innovation has already granted to CAHA 1.48 million euros of Next Generation EU funds to launch the project, charged to public support for ICTS within the framework of the 2021 Recovery, Transformation and Resilience Plan.



Calar Alto Observatory

Jesús Aceituno director @ caha.es

Instituto de Astrofísica de Andalucía

Jorge Iglesias jigelsia @ iaa.es

Calar Alto Observatory is one of the infrastructures that belong to the national map of Unique Scientific and Technical Infrastructures (Spanish acronym: ICTS), approved on March 11th, 2022, by the Science, Technology and Innovation Policy Council (CPCTI)


prensa  @  caha.es - Phone:(+34) 958230532

 miciu icts