Researchers report that a massive star underwent a silent transformation into a black hole after its supernova failed to occur.
According to a new study, a star in the Andromeda galaxy, 13 times more massive than the Sun, has become a black hole without the expected supernova explosion.
Typically, massive stars end their lives in a supernova, a dramatic event where the core collapses. The ensuing shockwave blows away the star’s outer layers, leaving behind a core that becomes either a black hole directly or a neutron star that may later collapse into one.
A Columbia University team, led by astronomer Kishalay De, proposes that NASA’s NEOWISE mission observed this much quieter black hole formation—without a supernova—in a galaxy 2.5 million light-years away.
Their theory, detailed in a paper published Thursday in the journal Science, accounts for the star M31-2014-DS1, which brightened in infrared light in 2014, faded dramatically by 2016, and had almost disappeared by 2023. The scientists suggest the material ejected from the star did not have enough speed to overcome the newborn black hole’s gravitational pull.
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“Ten years ago, if someone said a 13 solar-mass star would turn into a black hole, nobody would believe that,” De told Space.com. “It was completely outside what was considered the norm.”
Black holes possess such intense gravity that not even light can escape. Their mass warps space-time, bending light that passes near them. Radiation is also emitted when matter falls into a black hole, typically forming a fast-spinning accretion disk.
The researchers note that a faint infrared glow from the dust cloud around M31-2014-DS1’s location is still visible to powerful telescopes like the James Webb Space Telescope. They predict that as this cloud dissipates, X-rays from the currently hidden accretion disk will become detectable, which would verify their hypothesis.
“This is essentially as close as we can get to seeing the death of a massive star,” De stated. “In the end, I think it teaches us a lot more about stellar physics by not exploding.”