Image of the Abell 85 galaxy cluster, taken by the Hyper Suprime-Cam mounted on the Subaru telescope in Hawai‘i. The enhanced teal hazy overlay is intracluster light — the collective glow of innumerable stars stripped from their home galaxies and left to wander the vast intergalactic space. This ghostly glow is incredibly faint and difficult to detect, and is too faint to be seen in this image without the teal overlay, but Rubin Observatory’s 10-year survey will provide scientists with the data they need to detect intracluster light in thousands of galaxy clusters, unlocking clues to the evolutionary history of the Universe on large scales.