A Middleweight Black Hole is Hiding at the Center of a Giant Star Cluster

Typography

All known black holes fall into two categories: small, stellar-mass black holes weighing a few Suns, and supermassive black holes weighing millions or billions of Suns. Astronomers expect that intermediate-mass black holes weighing 100 - 10,000 Suns also exist, but so far no conclusive proof of such middleweights has been found. Today, astronomers are announcing new evidence that an intermediate-mass black hole (IMBH) weighing 2,200 Suns is hiding at the center of the globular star cluster 47 Tucanae.

All known black holes fall into two categories: small, stellar-mass black holes weighing a few Suns, and supermassive black holes weighing millions or billions of Suns. Astronomers expect that intermediate-mass black holes weighing 100 - 10,000 Suns also exist, but so far no conclusive proof of such middleweights has been found. Today, astronomers are announcing new evidence that an intermediate-mass black hole (IMBH) weighing 2,200 Suns is hiding at the center of the globular star cluster 47 Tucanae.

"We want to find intermediate-mass black holes because they are the missing link between stellar-mass and supermassive black holes. They may be the primordial seeds that grew into the monsters we see in the centers of galaxies today," says lead author Bulent Kiziltan of the Harvard-Smithsonian Center for Astrophysics (CfA).

This work appears in the Feb. 9, 2017, issue of the prestigious science journal Nature.

47 Tucanae is a 12-billion-year-old star cluster located 13,000 light-years from Earth in the southern constellation of Tucana the Toucan. It contains hundreds of thousands of stars in a ball only about 120 light-years in diameter. It also holds about two dozen pulsars that were important targets of this investigation.

Read more at Harvard-Smithsonian Center for Astrophysics

Photo credit: CfA / M. Weiss