An extremely remote celestial body in a still young Universe, one sixth the size of the present one. An object so dark that it is almost invisible, even to highly sophisticated instruments. Its nature has long been the subject of debate, but by means of surveys made with the ALMA interferometer, the SISSA research group led by Prof. Andrea Lapi that conducts research into the formation and evolution of galaxies has finally succeeded in identifying its main properties. Compact, and containing large quantities of interstellar dust, it is a young galaxy, forming stars at about 1000 times the rate of the Milky Way. The description of this galaxy will be useful for revealing more about this very distant object and indicating new approaches for the study of other ‘dark’ celestial bodies. The research just published in The Astrophysical Journal will also provide new insights for developing advanced models of galaxy formation and evolution.