The ESA Euclid mission aims to understand why the expansion of the Universe is accelerating and pin down the source responsible for the acceleration. It will uncover the very nature of dark energy and gravitation by measuring with exquisite accuracy the expansion rate of and the growth rate of structure formation in the Universe. To achieve its objectives Euclid will observe the distribution of dark matter in the Universe and its evolution over the last ten billion years by measuring the shapes of weakly distorted distant galaxies lensed by foreground cosmic structures. The shapes of lensed galaxies will be measured using the Euclid wide field imaging instrument VIS. In parallel, Euclid will analyse the properties of baryon acoustic oscillations and redshift space distortion and the distribution of clusters of galaxies by measuring the redshifts of galaxies with the NISP photometer and spectrometer instrument. The Euclid mission will observe one third of the sky (15,000 deg2) to collect data on several billion galaxies spread over the last ten billion years. In parallel to the space mission, the Euclid survey also comprises ground-based photometric and spectroscopic observations that will be used jointly with the Euclid satellite data to get photometric redshifts of billions of sources. Altogether the Euclid data set will be an exceptional gold mine for cosmology and fundamental physics but also for all fields in astrophysics. The presentation will describe the main scientific objectives and expected performances of the Euclid mission. The most recent forecasts and constraints on dark energy, gravity and dark matter will be presented as well as the expectations for the physics of inflation or neutrinos and the other domains of astronomy that will benefit from the Euclid mission data base.
42nd COSPAR Scientific Assembly
- Pub Date:
- July 2018