Spiral galaxy's supermassive black hole weighed for 1st time

Scientists have for the first time measured the precise mass of a black hole at center of distant spiral galaxy.

In a new proof-of-concept observation, astronomers used the Atacama Large Millimeter/submillimeter Array (ALMA) to measured the mass of the supermassive black hole at the center of NGC 1097, a barred spiral galaxy located approximately 45 million light-years away in the direction of the constellation Fornax.

The researchers determined that this galaxy harbors a black hole 140 million times more massive than our Sun. In comparison, the black hole at the center of the Milky Way is a lightweight, with a mass of just a few million times that of our Sun.

While NGC 4526 is a lenticular galaxy, NGC 1097 is a barred spiral galaxy. Recent observation results indicate the relationship between supermassive black hole mass and host galaxy properties varies depending on the type of galaxies, which makes it more important to derive accurate supermassive black hole masses in various types of galaxies, team leader Kyoko Onishi noted.

This is the first use of ALMA to make such a measurement for a spiral or barred spiral galaxy, co-author said Kartik Sheth.

Since current theories show that galaxies and their supermassive black holes evolve together, each affecting the growth of the other, this new measurement technique could shed light on the relationship between galaxies and their resident supermassive black holes.