By analyzing the images from the Ultraviolet Near Infrared Optical Northern Survey (UNIONS), an international team of astronomers has discovered a new compact satellite of the Milky Way, which received designation Ursa Major III/UNIONS 1. The newfound object turns out to be the least luminous known satellite of the Milky Way. The finding is reported in a paper published Nov. 16 on the pre-print server arXiv.