The Institut d'astrophysique de Paris wishes you an excellent year 2023!
Scheduled for launch next summer, the European Space Agency's Euclid satellite will try to resolve some of the enduring mysteries of modern cosmology — the nature of dark energy and of dark matter. To this end, Euclid will provide high-resolution optical-infrared imagesof the entire extragalactic sky, rivalling the Hubble space telescope, but over an area tens of thousands of times larger.
The nature of dark energy, which drives the accelerated expansion of the Universe, and the nature of dark matter, which is responsible for how the Universe is structured on the largest scales, are among the enduring mysteries in cosmology.
Over a decade ago, a group of researchers, led by members of the Institut d'astrophysique de Paris (IAP), the Laboratoire d'astrophysique de Marseille (LAM) and other European laboratories conceived an ambitious mission, Euclid space observatory of the European Space Agency (ESA), to probe the geometry of the Universe and help solve the mysteries of dark energy and dark matter. Euclid will achieve this by measuring the positions and shapes of galaxies over the visible extragalactic sky (outside the disk of the Milky Way) using two specially designed instruments. Euclid's high-resolution optical-infrared images will rival the Hubble space telescope, but the survey will cover an area tens of thousands of times larger.
The challenges in designing and constructing Euclid have been immense. For the mission to be a success, Euclid must have the most precise optical system ever flown in space, and this precision must be maintained during the six years that it will take to map the entire visible extragalactic sky. The volume of data produced by Euclid will also be the largest of any space mission, and the data processing “ground segment” (managed from France) is one of the most complex ever designed with very stringent data processing quality control requirements.
The IAP has participated in Euclid since its conception[1], leading both the mission and the teams of engineers who have been both perfecting the processing pipeline for the images that will be obtained with Euclid’s VIS instrument, and the generation of high-fidelity simulated images necessary to test those pipelines. These pipelines must convert Euclid’s raw data into images precise enough to measure the faint imprint that distant dark matter has on galaxy shapes. IAP scientists are also building on their expertise and long experience in galaxy clustering, numerical simulations, gravitational lensing, machine learning and cosmological parameter estimation to develop new tools to extract the maximum amount of scientific results from Euclid’s unique dataset.
[1] Science highlights on IAP's website in 2012 (in French): « La mission spatiale Euclid à la recherche de l'Univers sombre ».
Project manager and layout: Jean Mouette
Writing: Henry Joy McCracken, Valérie de Lapparent
December 2022