Stars Keep Surviving Close Encounters With Supermassive Black Holes

A star near the galaxy ESO 253-G003 has been getting raked across the edge of a supermassive black hole, over and over, for years. It's called ASASSN-14ko, and it has flared more than 30 times, at intervals so regular you could almost set a calendar by them: about every 114 days.

Each flare marks another close pass. The black hole's gravity is strong enough to strip material off the star's outer layers, and that stripped gas heats up and glows as it falls inward, producing the flash astronomers detect. Then the star swings away, battered but intact, and comes back around to do it again.

This is now a documented category of cosmic event: a repeating partial tidal disruption event, or rpTDE. "Tidal disruption" usually means a black hole fully ripping a star apart in one violent encounter. The words "partial" and "repeating" are what make this different. The star survives. It just keeps losing pieces.

Proving that a star genuinely comes back, rather than astronomers catching two unrelated flares that happen to look alike, is hard. In 2025, researchers found a second case, AT 2022dbl, where that proof came together: a flare, then a second flare roughly two years (about 700 days) later, from the exact same spot in the host galaxy, with a closely matching spectrum and temperature. That match is what lets astronomers say with real confidence that this is one star, struck twice, not two separate events.

Between ASASSN-14ko's 30-plus flares and AT 2022dbl's confirmed repeat, the picture holds up: some stars don't get destroyed by a close brush with a black hole. They get wounded, repeatedly, and somehow stay whole enough to orbit back for another pass. How many times a star can survive this before it finally gives way is still an open question, and one astronomers are now watching for in real time.