Gravitational-wave echoes indicate that the event horizon of a black hole may be more complicated than scientists currently estimate. Researchers from the University of Waterloo describe the first tentative detection of these echoes, produced by a microscopic quantum “fuzz” that surrounds newly created black holes. Researchers have reported the first tentative findings of these repeating echoes, providing experimental evidence that black holes may be radically different from what Einstein’s theory of relativity predicts, and lack event horizons. They used gravitational-wave data from the first observation of a neutron star collision, recorded by the LIGO/Virgo gravitational wave detectors. Scientists are now seeking more such examples to have a much more robust confirmation of these signals.