ALMA Measures Mass Of Supermassive Black Hole: 660 Million Times Larger Than Sun

A team of astronomers, using the Atacama Large Millimeter/submillimeter Array (ALMA), has come up with a way to measure precisely the mass of a supermassive black hole sitting in the center of the galaxy. This monster black hole, tagged as NGC 1332, is said to be 660 million bigger than the Sun.

According to Astronomy, the team determined the exact mass of the supermassive black hole by exploring the interstellar gas and stars that are encircling it and the gravitational pull of the said black hole on them. NGC 1332 is located 73 million light years away from Earth.

“Measuring the mass of a black hole accurately is very challenging, even with the most powerful telescopes on Earth or in space,” said lead astronomer Aaron Barth from the University of California.

Barth and his team measured the speed of carbon monoxide around the monster black hole's center using ALMA, which has the ability to observe the black hole's disk.

“To calculate the mass of a black hole in a galaxy’s center, we need to measure the speed of something orbiting around it. For a precise measurement, we need to zoom into the very center of a galaxy where the black hole’s gravitational pull is the dominant force," Barth told UCI News. "ALMA is a fantastic new tool for carrying out these observations."

ALMA revealed that the gas near the center of the black hole's disk is traveling at a speed of 500 kilometers per second. Analyzing this from simulations, Barth concluded that the supermassive black hole NGC 1332 is 660 million times bigger than the Sun.

To compare how large NGC 1332 is, it's approximately 150 times greater than the black hole found in the center of the Milky Way.

ALMA, the powerful facility that the team used, is located in the Atacama Desert of Northern Chile, 5,000 meters above sea level. The said tool is composed of 66 radio telescopes that can zoom in and observe even the tiniest wavelengths.