February 21, 2021 For the first time, astronomers have detected the presence of a throng of black holes crowding near the center of an ancient globular cluster. In this episode of Space Sparks, ESA/Hubble summarizes their findings. Sometimes in science when you set out to find something you had predicted, you instead find something quite different. This was the case recently when astronomers using the Hubble Space Telescope examined the core of a globular cluster, a “ball” of densely packed old stars named NGC 6397, looking for one central intermediate-mass black hole. Instead they unexpectedly found a whole swarm of small black holes, as reported by NASA and ESA on February 11, 2021.