When mass is so strongly concentrated that not even light can escape its gravitational field, physicists call this phenomenon a black hole. In reality, however, the name doesn’t quite fit its true physical nature. This is because some radiation, so-called Hawking radiation, is indeed emitted from a black hole. In addition, black holes set their surroundings in so much turmoil that in no way do they remain invisible: the matter falling into the hole forms an accretion disk around it, there are all kinds of swirling, turbulent magnetic fields – there’s little reason to fear falling into a black…