The quest to understand the evolution and fundamental nature of the Universe has taken a significant step forward with the Euclid satellite, launched in July 2023. Euclid’s mission is to explore some of the biggest mysteries in cosmology: gravity, dark matter, and dark energy. An extensive map of the Universe’s large-scale structure has been created to achieve this by observing billions of galaxies up to 10 billion light-years away, across more than a third of the sky. In March 2025, Euclid released its first dataset, offering a wealth of information. This initial release includes three large mosaics featuring galaxy clusters, active galactic nuclei, and transient cosmic events, alongside a groundbreaking classification of over 380,000 galaxies and 500 gravitational lens candidates.
The University of Edinburgh plays a crucial role in this mission, processing Euclid’s massive data streams before UK research teams analyse them. These teams have already made remarkable discoveries, detecting rare cosmic events that were once nearly impossible to find, observing the remnants of dying stars long after they disappeared from Earth’s view, and uncovering numerous supermassive black holes.
Looking forward, a much larger data release is planned for October 2026, which is expected to shed new light on the nature of dark energy. With Euclid proving to be an unprecedented source of astronomical data, the mission is ushering in a new era of space exploration and scientific breakthroughs.
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