Swiss Involvement with the European Southern Observatory 

The stellar binary R Aquarii in a turbulent dance. (Credit: ESO/Schmid et al.)

Switzerland joined ESO as a Member State on 1 March 1982. As a country that’s been with ESO for many years, its community of scientists and engineers has contributed to ESO projects in many key ways, from participating in discoveries to playing important roles in developing instruments, many related to the world's foremost planet hunters.  

Switzerland currently contributes 4.23% of ESO’s revenue (2021 contribution), worth 8 123 000 EUR. 

As of mid 2022, there are four Swiss nationals employed at ESO, three in Germany and one in Chile. Furthermore, ESO has awarded four studentships and four fellowships to Swiss nationals since 2004. 

Switzerland is represented in the various ESO governing and advisory bodies by astronomers and policy experts; the current Swiss representatives of ESO’s various committees with national representation can be found here. 

The ESO Science Outreach Network (ESON) includes Swiss representatives who act as ESO’s media and outreach local contacts. 

Here follows some information about Switzerland's involvement with ESO. 

Discoveries by Switzerland-based astronomers using ESO telescopes 

Swiss researchers and those based at Swiss institutions have been involved in important discoveries using ESO facilities and telescopes hosted at ESO’s observatories. These include 

• A team led by Adrien Leleu (Université de Genève, University of Bern) that discovered a six-exoplanet system where five of the planets are locked in a rare rhythm around their central star. The researchers believe the system could provide important clues about how planets, including those in the Solar System, form and evolve.
• David Ehrenreich (University of Geneva) who led a study that discovered an exoplanet with a dayside temperature of over 2400 degrees Celsius: hot enough to vaporise metals. Based on observations with ESPRESSO on ESO’s Very Large Telescope (VLT), the team believes that iron could be raining down on the surface of the planet.
• The sharpest ever images of the turbulent stellar binary R Aquarii were taken using the Zurich IMaging POLarimeter (ZIMPOL) component of the SPHERE instrument on the VLT.  The team capturing this stunning dance was led by H. M. Schmid (ETH Zurich, Institute for Astronomy).
• A team led by Simon L. Grimm (University of Bern) that discovered seven planets orbiting the nearby ultra-cool dwarf star TRAPPIST-1. These planets were found to be made mostly of rock, and some could potentially hold more water than Earth. 

Swiss involvement in ESO instruments and telescopes at ESO sites 

Switzerland has contributed to many aspects of ESO, including the technology behind instruments, ESO telescopes and telescopes based at ESO sites. These include 

• The FLAMES (Fibre Large Array Multi Element Spectrograph) instrument, which was designed and built by an international consortium of research institutes where the Observatoire de Genève has been key in the development. FLAMES is installed on the Unit Telescope 2 of ESO’s VLT. 
• The HARPS instrument, which was designed and built by an international consortium of research institutes, led by the Observatoire de Genève. The instrument is mounted at the ESO 3.6-metre telescope at La Silla Observatory, and is one of the most successful planet finders in the history of astronomy, having discovered hundreds of new exoplanets.  
• The development of HARPS’ successor, ESPRESSO, the Echelle SPectrograph for Rocky Exoplanet and Stable Spectroscopic Observations, which was led by the Observatoire de Genève and the University of Bern. Sitting at the VLT, its primary goal of ESPRESSO is to make very high precision radial velocity measurements of solar-type stars to search for rocky planets. 
• The Swiss 1.2-metre Leonhard Euler Telescope, which is hosted at ESO’s La Silla Observatory. It was built and is operated by the Observatoire de Genève. It was used in conjunction with the CORALIE instrument, decommissioned in 2006, which was developed through a collaboration between the Observatoire de Genève and the Haute Provence Observatory (OHP) in France. The purpose of the spectrograph is to conduct high precision radial velocity measurements to search for large exoplanets in the southern celestial hemisphere. 

Swiss involvement in ELT instruments 

• The MOSAIC instrument at ESO’s upcoming Extremely Large Telescope (ELT) will peer closer at distant galaxies at the very edge of the observable Universe. MOSAIC is being developed by a consortium in which Observatoire de Genève participates.  
• The ELT instrument METIS, named after the Greek goddess of wisdom, will be able to study a wide range of astronomical objects, from the Solar system to distant Galaxies. METIS is a collaboration between several astronomy institutes in Europe, including ETH Zürich that leads the science development of the instrument.  
• ANDES, the instrument that will study astronomical objects with unprecedented sensitivity, will also be a first-generation ELT instrument. Université de Genève and Universität Bern participate in the consortium that develops ANDES.  
• ETH Zürich is also a key partner in a design study for a future ELT instrument, called EPICS or ELT-PCS, capable of directly imaging exoplanets.  

Swiss industry and technology contributions to ESO 

Switzerland has contributed to many aspects of ESO, with many contracts awarded to Swiss industry, including 

• The Swiss company Data Conversion Service S.A., which has been awarded several ESO contracts for general IT support and services. 
• The company TURBOMACH S.A., which provided a dual fuel power generator for Paranal before the observatory switched to renewable energy. 
• Schott Suisse S.A., which conducted optical treatment to parts of the MATISSE instrument on ESO’s VLT Interferometer.