Galaxy cluster at the edge of the Universe

Astronomers have found the most distant galaxy cluster ever seen: the sexily-named SXDF-XCLJ0218-0510.

In the case of this newly found cluster, the light we see left it 9.6 billion years ago - making it 400 million light years farther away than the next-most distant cluster ever seen. The Universe itself is only 13.7 billion years old, so we're seeing this structure as it was not too long after it formed.