By Graeme Murray & Isobel Williams The oldest ever black hole has been discovered, and astronomers claimed it dates back to the very dawn of the universe. Researchers spotted the 13-billion-year-old phenomenon from 400 million years after the Big Bang. They claimed it appeared to be ‘eating’ its host galaxy to death. The black hole is a few million times the mass of our Sun. The discovery challenged scientists’ assumptions on how they form and grow because they should not be that size so early on in the universe. If it grew in an expected way, the newly detected black hole would take about a b…