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.Distance is approximately 3.5 billion light-years.

The galaxies in the cluster make up less than five percent of its mass.The gas (around 20 percent) 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.

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Frontier Fields Program Images