Asked by: Tim Reynolds, Canterbury
Supermassive black holes reside deep in the cores of galaxies and create huge amounts of X-ray emissions as they continually devour material. Such objects are thought to hide in the heart of all galaxies. But recently, astronomers were surprised to find that one such black hole, in the Sculptor Galaxy (NGC 253) (pictured), appears to have fallen asleep!
Observations by NASA’s NuSTAR spacecraft have failed to detect X-ray emission from NGC 253, whereas observations a decade ago by the Chandra X-ray Observatory showed telltale signs of the black hole feeding. Astronomers are not yet clear as to whether the black hole has become dormant or whether the Chandra observations were from a different source of X-rays.
Researchers are now hoping the black hole will wake from its slumber, and they’ll be ready to catch it if it does!
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