Scientists discovered a galactic ghost — but there’s nothing paranormal about it

It’s a classic Halloween tale. A group of ghost hunters visit a grand old house that is rumoured to be haunted. But after thoroughly exploring, they leave disappointed: there are no ghosts to be seen. Only later, when looking through their photographs of the place do they notice the mysterious apparition on the stairs. It was there all the time. In our new work, published in Nature, we were shocked to discover an apparition of galactic proportions when looking at a familiar galaxy. The fi