Galaxy cluster SPT-CL J0615−5746, the foreground object that created the gravitational lens. Image Credit: ESA/Webb, NASA & CSA, L. Bradley (STScI), A. Adamo (Stockholm University) and the Cosmic Spring collaboration =============================================================================== Astronomers have discovered the most distant, and so the oldest, known stellar clusters. This is the first time astronomers have seen star clusters from before the first half a billion years of the Universe. The light of these gravitationally bound groups of stars comes to us from just 460 million years after the Big Bang. Two factors have been crucial to the discovery. The extremely keen infrared eye of...