English: ESA's Euclid mission is designed to explore the composition and evolution of the dark Universe. The space telescope will create a great map of the large-scale structure of the Universe across space and time by observing billions of galaxies out to 10 billion light-years, across more than a third of the sky. Euclid will explore how the Universe has expanded and how structure has formed over cosmic history, revealing more about the role of gravity and the nature of dark energy and dark matter.
[Image description: Artist impression of the Euclid mission in space. The spacecraft is white and gold and consists of three main elements: a flat sunshield, a large cylinder where the light from space will enter, and a 'boxy' bottom containing the instruments. The spacecraft is shown half in the shadow, because the sunshield will always be faced in the direction of the Sun and thus protecting the telescope from the light of the Sun. The background is a realistic representation of a deep field view of the night sky, with many galaxies visible. On the bottom half of the image, an artistic representation of the cosmic web is overlayed over the galaxies. The cosmic web is the scaffolding of the cosmos on which galaxies are built, consisting primarily of dark matter and laced with gas. The cosmic web is here represented with a grid and a two-dimensional representation of a cosmological simulation.]