Astronomers have discovered a long-missing element of a galactic collision involving the Perseus galaxy cluster, located 240 million light-years from Earth.
This element, a newly detected "subcluster," is 1.4 million light-years to the west of NGC 1275, the central galaxy of the Perseus cluster. These two elements seem to be connected by a faint "bridge" of material.
The structural backbone of this bridge is dark matter, the universe's most mysterious "stuff." Dark matter remains effectively invisible by not interacting with light, but its interaction with gravity has helped to shape galactic structures.
