Pan: Cosmic leviathan

This particular galaxy cluster is called eMACS J1823.1+7822, and lies almost nine billion light-years away in the constellation Draco. It is one of five exceptionally massive galaxy clusters explored by Hubble in the hopes of measuring the strengths of these gravitational lenses and providing insights into the distribution of dark matter in galaxy clusters. Strong gravitational lenses like eMACS J1823.1+7822 can help astronomers study distant galaxies by acting as vast natural telescopes which magnify objects that would otherwise be too faint or distant to resolve.

More information and download options: http://esahubble.org/videos/potw2319a/

Credit:
ESA/Hubble & NASA, H. Ebeling
Music: Stellardrone - Billions and Billions