How could the Universe form such dense and extremely hot structures only 1.4 billion years after the Big Bang? This question ...

Astronomers have discovered a galaxy cluster burning five times hotter than theoretical models predicted, just 1.4 billion ...

Astronomers found a young galaxy cluster with unexpectedly hot gas, suggesting cosmic structures formed faster than once ...

The Champagne Cluster is a rare and beautiful example of two galaxy clusters smashing together. Its festive name comes from both its New Year’s Eve discovery and its bubbly appearance in space. Images ...

Galaxy clusters are formed by a dense packing of many galaxies, making them the most massive structures in the universe.

The largest structures in the universe are galaxy clusters—groups of galaxies held together by gravity. Their developmental ...