Credit: NASA, ESA, and P. Jeffries (STScI)
This illustration shows the final stages in the life of a supermassive star that fails to explode as a supernova but instead implodes under gravity to form a black hole. From left to right: the massive star has evolved to a red supergiant, the envelope of the star is ejected and expands,
producing a cold, red transient source surrounding the newly formed black hole. Some residual material may fall onto the black hole, as illustrated by the stream and the disk, potentially powering some optical
and infrared emissions years after the collapse.