Exploring Euclid's Korsch configuration mirrors

The 1.2-m diameter main mirror of ESA's Euclid mission to unveil the dark universe, seen during assembly, integration and testing. Using this mirror, the spacecraft will map the 3D distribution of billions of galaxies up to 10 billion light years away—looking beyond the Milky Way galaxy to image around a third of the observable universe. By revealing the universe's large-scale structure, and its pattern of expansion, the mission will cast light on the mysterious dark energy and dark matter making up 95% of the cosmos.