Researchers measure black hole with ‘unprecedented accuracy’

Thanks to the powerful Atacama Large Millimeter/submillimeter Array (ALMA) in Chile, a team of astronomers managed to measure the mass of a nearby supermassive black hole with what they are calling “unprecedented accuracy,” according to a newly published study.

Andrew J. Baker, an associate professor at Rutgers University in New Jersey, and his fellow researchers used the ALMA telescopes to measure the black hole located at the center of NGC 1332, a galaxy that is located approximately 73 million light years from Earth.

As reported Thursday in the Astrophysical Journal Letters, the researchers discovered that the black hole is roughly 660 million times more massive than the sun, and is surrounded by a cloud of gas that circles around it at speeds of more than million miles per hour. They noted that these measurements were made possible by ALMA’s high-resolution observations of carbon monoxide emissions from the high-speed gas disk surrounding the black hole.

“This has been a very active area of research for the last 20 years, trying to characterize the masses of black holes at the centers of galaxies,” Baker, who started studying black holes as a graduate student, said in a statement. “This is a case where new instrumentation has allowed us to make an important new advance in terms of what we can say scientifically.”

What precise data can tell us about black holes and their galaxies

Black holes, massive regions of space-time that are so dense that their gravitational pull typically attracts anything that ventures close enough to them (including light), can form after matter from an exploding star condenses due to gravity, said Baker, who is part of the Astrophysics Group in the Rutgers School of Arts and Sciences’ Department of Physics and Astronomy.

Once they have formed, these black holes can grow to supermassive size by consuming gas, stars and even other black holes. However, as Baker pointed out, objects such as stars can travel near a black hole without being swallowed up, provided they have stable orbits and are moving quickly enough to avoid capture.

“Just because there’s a black hole in your neighborhood, it does not act like a cosmic vacuum cleaner… The black hole at the center of the Milky Way, which is the biggest one in our own galaxy, is many thousands of light years away from us. We’re not going to get sucked in,” the professor explained. Scientists believe that there is a black hole at the center of most if not all massive galaxies, and are eager to learn more about how they form and evolve.

The data collected from NGC 1332’s black hole using the ALMA telescopes could shed new light on how galaxies and their central supermassive black holes form, said Baker. For instance, the ratio of a black hole’s mass to that of its galaxy is essential to understanding their makeup, as research has suggested that the growth of both galaxies and black holes are coordinated.

In order to fully understand how galaxies form, science needs to know how black holes form. A key part of this, the study authors wrote, is to determine the exact masses of these black holes, as this knowledge will allow researchers to determine if they are growing as quickly as their host galaxy. Unless the black hole mass measurements are extremely accurate, as was the case in this new paper, scientists will be unable to draw any concrete conclusions.

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Image credit: Carnegie-Irvine Galaxy Survey