A star that was photographed by the Hubble Space Telescope disappeared and nobody knows why!
This is the star in 2007, but by 2015 – it was gone. It disappeared from optical view.
There was a spike in luminosity in 2009, but not enough to be caused by a supernova. It could be a failed Supernova.
One hypothesis is that the core of the star collapsed to form a black hole. And if that is what happened, it is the first time that a black hole formation has ever been observed.
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