The ESA “Cosmic Vision” Euclid space telescope mission

The Swiss Space Office, EPFL, the University of Geneva, the University of Zurich, the University of Applied Sciences and Arts Northwestern Switzerland, and Brugg HET are strongly involved in the design of the Euclid space telescope mission (a study of the accelerating expansion of the universe), that has been selected by ESA (European Space Agency) in the framework of  the “Cosmic Vision” program.  This mission is scheduled to be launched in July 2023.

The origin of the accelerating expansion of the universe is one of the most fascinating challenges of 21st century cosmology and fundamental physics. Astronomers and physicists are convinced  that finding its very nature will revolutionise our understanding  of quantum physics, gravity and the physics of the very early universe.

Euclid is an ESA survey space mission designed to understand the origin of the universe’s accelerating expansion that physicists and  astronomers call “Dark Energy”. Current observations show  that dark energy composes more than 70% of the total energy of  the present-day universe and is therefore driving its evolution.  Euclid will observe several billions of galaxies over a large  fraction of the sky (15’000 square degrees) and will  track  the observational signatures of dark energy, dark matter, and gravity on the geometry of the universe and the  cosmic history of structure formation. The 2011 Nobel prize in Physics was awarded to the three discoverers of the observational evidence for the accelerated expansion of the universe, which is a consequence of the  presence  of dark energy.

By measuring the apparent shapes and the distribution of galaxies in the universe, astronomers will study dark energy and determine whether the theory of general relativity is still valid on scales beyond billions of light years.  To achieve this, the satellite will be equipped with a visible imager  (VIS) and a near-infrared spectro-imager (NISP) developed by a European consortium comprising more than 110 laboratories and 1400 scientists in Europe, led by Yannick Mellier from the Institut d’Astrophysique de Paris (IAP). The consortium is also in charge of the scientific ground segment to produce and analyse the data obtained with the Euclid instruments.

Besides ESA, the leading contributing countries forming the Euclid Mission Consortium are Austria, Denmark, Italy, Finland, France, Germany, the Netherlands, Norway, Romania, Spain, Switzerland and the UK, with a contribution from laboratories in the USA.

Several Swiss partners are contributing to Euclid: the Swiss Space Office, the Swiss Federal Institute of Technology Lausanne (EPFL), the University of Geneva (UniGE), the University of Zurich (UniZH), the University of Applied Sciences and Arts Northwestern Switzerland (FHNW), and Brugg HET.