When black holes or neutron stars merge, they strum space, broadcasting gravitational waves — a chirp predicted by Einstein. Detectors like LIGO capture this cosmic ringtone, its pitch encoding the masses. Yet, there's a silent interval in the cosmic scale: objects from 2 to 5 Suns are almost never heard. This lower mass gap lies between the heaviest neutron stars and lightest black holes.

GWSkyNet-MassGap, a neural network, listens to the gravitational wave chirp and judges if a merger includes a neutron star or a gap object — like naming instruments in an orchestra. It's accurate for loud signals but can mishear the mass split in faint ones. If neutron stars collide, telescopes catch a kilonova forging gold; black hole mergers stay dark. Sifting gravitational wave catalogs, it spotlights rare candidates. The gap may hide surprises — perhaps quark-matter ghosts that are neither star nor hole.