For once, searching for something and not finding it turned into a revolutionary discovery. This is what happened to Alejandro Benitez-Llambay, a researcher from the Department of Physics at the University of Milano-Bicocca, who, along with astronomers from Canada and the United States, discovered Cloud-9, a dark matter halo devoid of stars in the heart of the cosmos, 14 million light-years away. Thanks to an investigation utilizing the world's most advanced observatories, Cloud-9 has been identified as the first confirmed candidate for RELHIC, an astrophysical object theorized by the cosmological model but previously unobserved. The results were published in The Astrophysical Journal Letters. "With these observations, we have verified that, despite its mass and the presence of gas, Cloud-9 is not a galaxy: within this region, spanning over 1.4 kpc (4,500 light-years), no stars are visible", explains Alejandro Benitez-Llambay. This is the distinguishing property that makes it the first certain candidate for RELHIC (Reionization-Limited H I Cloud). This is a type of dark matter halo that, despite extending over 1.4 kiloparsecs and contains huge amounts of neutral hydrogen (HI), is devoid of stars. These objects had never been observed before: they would be massive enough to retain part of their gas but not enough to overcome thermal pressure and trigger star formation, creating what is called a “failed galaxy” or “ghost galaxy". The search for these elusive objects required a new generation of telescopes with unprecedented sensitivity.