In 2009, astronomers noticed a massive star—about 25 times the Sun’s mass—brighten for several months, expecting it to end in a supernova. Instead, it just… faded away. No explosion, no bright flash—just gone. One explanation: it collapsed directly into a black hole. Normally, a dying star releases energy as a final supernova before collapsing, but this one might have been so massive that gravity won instantly, swallowing the entire star before it could put on a show. If that’s true, there could be black holes out there forming in total silence. But a later JWST study found the source looks more like two stars that merged, and it can’t rule out the black hole, so the mystery is still open.
~25 times the Sun's mass
Mass of the star that vanished