"The Fat One" - The Largest Gravity Bound Structure in The Universe

'El Gordo,' Galaxy With Mass 2 Quadrillion Times the Sun's, Discovered via NPR

Astronomers in Chile at Rutgers University have discovered the "most massive" galaxy cluster ever seen in the universe. "El Gordo" is 2,000,000,000,000,000 quadrillion (15 zeros!) suns and 7 billion light years away. A galaxy cluster is made up of hundreds of thousands of galaxies bound together by gravity. They are formed when clouds of hot gas (30-100 million degrees Celsius) envelop galaxies and fill in the space between them. This is does not provide enough mass to hold together the galaxies, so scientists believe dark matter is required to provide the extra gravity. "El Gordo" is important because it allows astronomers to study how the universe is growing and it is a really big laboratory for astrophysicists. "El Gordo" is forming a picture on how the universe formed by providing a model to measure the amount of dark matter and dark energy that makes up the universe. The astronomers also had the chance to watch two cluster merge together. The two clusters collided and "crushed" each other when hot gas from one cluster was absorbed into the other structure. So essentially, one cluster passed through another cluster.

The whole idea that hundreds of thousands of galaxies 'cluster' together out there in deep space is completely mind blowing to me. It's really cool that this cluster of galaxies can help us in finding out how the universe formed and how it is growing.