An article published in the journal “Astronomy & Astrophysics” reports evidence of the presence of a group of black holes in the globular cluster NGC 6397. Eduardo Vitral and Gary A. Mamon of the Institut d’Astrophysique de Paris (IAP) used observations conducted with the Hubble Space Telescope and the Gaia space probe to study the core of NGC 6397 expecting to find evidence of the presence of an intermediate-mass black hole that was a hidden mass, but the analyzes of the star movements within the cluster indicated the presence of various stellar-mass black holes.