Abell 2744
Abell 2744, nicknamed Pandora's Cluster, is a giant galaxy cluster resulting from the simultaneous pile-up of at least four separate, smaller galaxy clusters that took place over a span of 350 million years. The galaxies in the cluster make up less than five percent of its mass. The gas is so hot that it shines only in X-rays. Dark matter makes up around 75 percent of the cluster's mass.
This cluster also shows a radio halo along with several other Abell clusters. It has a strong central halo, along with an extended tail, which could either be relic radiation, or an extension of the central halo.
Renato Dupke, a member of the team that discovered the Cluster, explained the origin of the name in an interview: "We nicknamed it ‘Pandora's Cluster’ because so many different and strange phenomena were unleashed by the collision."Gallery