Hubble Photographs a Galaxy with a Supermassive Black Hole Core

Galaxy NGC 7172

In a new photo captured by Hubble, what appears to be a calm spiral galaxy belies the supermassive black hole at its nucleus.

The photo, captured by the Hubble Space Telescope, shows a galaxy that is surrounded by dark tendrils of dust that thread across and around the core. That dust blocks a clean view of the galaxy’s glowing heart and makes it appear as though it is nothing more than a normal spiral galaxy in this view of it from its side.

When astronomers took a closer look at the galaxy, which is known as NGC 7172 and it lies about 110 million light-years from Earth in the constellation Piscis Austrinus, they realized that there was more at play here than what originally meets the eye. NGC 7172 is what is known as a Seyfert galaxy, which is the kind of galaxy that has a bright, luminous galactic nucleus that is powered by matter that is forming around and onto a supermassive black hole.

The photo was taken from two sets of Hubble observations that were both propsoed to study nearby active galactic nuclei, NASA explains. The image also combines data from two of Hubble’s cameras: the Advanced Camera for Surveys and Wide Field Camera 3.

Black Holes are Tricky to Observe

Black holes by their very nature impossible to photograph directly by traditional means as they do not emit any light on any spectrum, as their gravity is so vast that nothing can escape it once it is absorbed. That said, they do become visible based on the light emitted by surrounding objects. In a previous, groundbreaking photo of a black hole, the hole itself is of course not visible but the bright jets of energy can be seen surrounding the edge as they dip in.

In August of last year, astrophysicists made history by successfully observing the light that was coming from behind a black hole. That observation was the first of its kind and proved Albert Einstein’s theory that huge objects can warp space since no light can pass through a black hole and come out the other side.

This is not the first galaxy that features a black hole that Hubble has photographed this year. In January, Hubble discovered a black hole at the center of a dwarf galaxy that was actually forming stars, not absorbing them.


Image credits: ESA/Hubble and NASA, D. J. Rosario, A. Barth; Acknowledgment: L. Shatz

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