The star that later exploded as supernova 1987A put on a gas ring twenty thousand years before the blast. Not one ring — three. The star's light, passing through the rings, scattered like a flashlight beam in fog. For an observer positioned exactly in the plane of the equatorial ring, the star nearly vanished: its brightness dropped to five percent. Today, such an event would be called a 'failed supernova'—a star that dimmed but didn't explode. But it was simply hiding behind its own ring.
After a few thousand years, the ring became transparent, and the star returned to normal brightness. But astronomers searching for black holes born without a bang might mistake such a temporary dimming for a real collapse. The work shows that some 'failed supernovae' may simply be stars playing hide-and-seek. This matters for statistics: if we confuse one with the other, we miscount how often massive stars die without exploding.
The equatorial ring of Supernova 1987A is expanding at 10.3 km/s—30 times slower than the International Space Station's orbital speed. Over 20,000 years, it has inflated to a radius of about 1.5×$10^{18}$ cm, roughly 100 times the distance from the Sun to Earth.