NGC 4696

Astronomers haven’t “seen” the black hole at the center of NGC 4696, a galaxy in the constellation Centaurus. Yet the black hole’s impact on the surrounding environment is quite clear. It produces shock waves, blows bubbles, and pushes hot gas into the fringes of the galaxy and beyond.

NGC 4696 is the brightest member of the Centaurus galaxy cluster. It’s a giant elliptical galaxy, which is bigger and heavier than our home galaxy, the Milky Way.

Like most big galaxies, NGC 4696 appears to have a supermassive black hole at its center. Astronomers haven’t measured its mass, although it’s much heavier than the black hole at the heart of the Milky Way.

Looking at the galaxy in X-rays and radio waves revealed that the black hole appears to “erupt” every five million to 10 million years. The eruptions probably come from a disk of superhot gas around the black hole. Something causes the disk to produce powerful “jets.” These high-speed streamers pump energy and particles into the space around the black hole.

The jets appear to race beyond the borders of NGC 4696. They clear out big bubbles in the hot gas between galaxies. And they push clouds of gas and dust out of the galaxy, preventing the clouds from forming new stars.

As the jets shut down, though, gas and dust near the black hole may get cooler. Some of the material then may fall into the disk around the black hole — perhaps triggering the next outburst.

Script by Damond Benningfield