Intracluster light in Abell S1063
Abell S1063, a galaxy cluster, was observed by the NASA/ESA Hubble Space Telescope as part of the Frontier Fields programme. The huge mass of the cluster – containing both baryonic matter and dark matter – acts as cosmic magnification glass and deforms objects behind it. In the past astronomers used this gravitational lensing effect to calculate the distribution of dark matter in galaxy clusters.
A more accurate and faster way, however, is to study the intracluster light (visible in blue), which follows the distribution of dark matter.