Professor Studies Star-Forming Role of Black Holes

Professor Studies Star-Forming Role of Black Holes

Black holes are well-known for their destructive powers, consuming nearly everything in their path with reckless abandon. With the gravitational pull of millions of Suns confined to a single object, they are the strongest sources of gravity in the Universe; light itself cannot escape their pull.

Chris Fragile

However, black holes may also play a more constructive role, occasionally even being responsible for the birth of new stars.

Now, computer simulations performed by physics and astronomy professor Chris Fragile and his team at the College of Charleston are finding answers concerning the relationship between star formation and black holes.

A relatively nearby star-forming region, known as Minkowski’s Object (M.O.), is a prime example of this progenitive power of black holes. Located approximately 260 million light years from earth, M.O. resides at the end of a radio jet coming from the supermassive black hole in the center of the neighboring galaxy, NGC 541.

Radio jets are streams of fast-moving particles spewed out by the incredible power of black holes that are actively devouring gas.

Earlier observations by the Very Large Array (VLA) and Hubble Space Telescope (HST) showed that the radio jet from NGC 541 is interacting with M.O., a formerly serene cloud of gas that is now undergoing a burst of star formation at the interaction site. Those observations confirmed that M.O. is a rare, present-day example of “jet-induced star formation,” in which the jet triggers the compression and cooling necessary to form stars.

A snapshot from a computer simulation of Minkowski’s Object. Red colors correspond to jet material entering from the left; blue corresponds to undisturbed cloud material; and green corresponds to cold, compressed gas that is actively forming stars.

Using the Stampede supercomputer at the Texas Advanced Computing Center (TACC), Fragile’s group simulated various cases of jets of gas colliding with inactive clouds. In some cases, the jet overpowered the cloud and dispersed the gas before stars could form. In other cases, significant star formation was seen.

In one case, the results closely matched all the key observables of M.O.: the distribution of stars and gas, the total mass in stars, the measured star formation rate, and the proportions of cold and warm gases.

Fragile believes this research is helping scientists better understand the various roles, both constructive and destructive, that black holes play in the lives of galaxies.

“This project represents a compelling case for synergy between observers and numericists,” says Fragile. “We are using both approaches to better understand this specific object, but also star formation more generally.”

Information on this research is published in the current edition of the Astrophysical Journal.