Star in Andromeda Collapses Into Black Hole
Astronomers observed a star in the Andromeda galaxy collapsing directly into a black hole, an event described as a rare spectacle. Other recent celestial events include the appearance of comet C 2024 E1, the discovery of a cold, Earth-sized exoplanet, and a record-long gamma-ray burst theorized to be a black hole consuming a helium star.
- The star, known as M31-2014-DS1, was located 2.5 million light-years away in the Andromeda Galaxy. Before its collapse, it had shed much of its initial mass of roughly 13 times that of the Sun, weighing only about 5 solar masses at the end of its life. - This event is a prime example of a "failed supernova," a long-theorized but rarely observed process where a massive star's core collapses into a black hole without the violent, brilliant explosion that typically follows. - The discovery was made by analyzing archival data from NASA's NEOWISE mission, which was originally designed to hunt for asteroids. The data showed the star brightening in infrared light for several years starting in 2014 before it faded and vanished from view in optical light. - A team led by astronomer Kishalay De of the Flatiron Institute confirmed the star's disappearance using follow-up observations from the W. M. Keck Observatory, the Hubble Space Telescope, and the MMT Observatory. - By 2023, the star had faded in visible light by a factor of about 10,000, effectively disappearing. A faint infrared glow remains, believed to be from the dusty shell of material ejected by the star before its final collapse. - This event provides a clearer view of a direct collapse than a previous candidate, N6946-BH1, because the Andromeda galaxy is about 10 times closer to us than that star's host galaxy, NGC 6946. - Understanding the frequency of such "failed supernovae" is critical for accurately estimating the population of stellar-mass black holes and refining models of how chemical elements are distributed through galaxies, as these quiet collapses return less material to space than a traditional supernova.
