The light and Dark Universe

For centuries, astronomers have sought to learn more about the luminous sources of the cosmos – things like stars and galaxies. But 95% of the Universe appears to be made up of unknown 'dark' matter and energy: elusive substances that influence the shape, motion and distribution of visible sources. Because dark matter and energy do not emit, absorb or reflect any light, they are hard to study, and scientists do not know yet what they actually are.

By mapping billions of galaxies, Euclid will reveal how matter is distributed across the cosmos and how the fabric of the Universe has evolved over time. Because dark matter and energy influence the visible sources, this map will help astronomers finally reveal the nature of 'the other 95%’.

Image description: Artist’s impression of Euclid in space, peering beyond the Milky Way galaxy.