- A massive star in the Andromeda Galaxy, M31-2014-DS1, collapsed into a black hole without a supernova explosion.
- The star's brightness dropped sharply in 2016 and nearly vanished by 2022-2023, leaving only a faint glow in mid-infrared light.
- Observations suggest the star's core collapsed under gravity, forming a black hole while its outer layers were gradually expelled.
- This event provides rare insights into how some massive stars quietly transition into black holes, bypassing supernovae.
- Convection in the star's outer layers played a key role in the slow expulsion of material, leading to a prolonged infrared glow.
- The findings challenge existing theories and suggest a broader category of failed supernovae that result in black holes.
- The study combines data from multiple telescopes, including NASA's NEOWISE mission, spanning nearly two decades.
- Researchers estimate only about 1% of the star's outer envelope ultimately feeds the black hole, producing the observed faint light.
- The event offers a benchmark for understanding stellar black hole formation and may explain why some stars explode while others collapse quietly.