Euclid -- The Dark Universe detective

Euclid is a recently launched medium-class mission by the European Space Agency (ESA) designed to measure cosmological parameters, test the cosmological standard model, and explore the nature of dark matter and dark energy. To this end, Euclid conducts a survey of up to 14000 square degrees of the extra-galactic sky and obtains optical and near-infrared photometric measurements for more than a billion galaxies as well as near-infrared slitless spectroscopy for more than 35 million galaxies. These observations will be used to estimate galaxy clustering and cosmic shear. It is expected that Euclid will achieve percent-level constraints on the Dark Energy equation of state parameter. The survey will also be exploited with a range of other cosmological probes and prove revolutionary for non-cosmological science.