Gigantic Black Hole Wreaks Havoc for Hundreds of Million Years in the Perseus Galaxy Cluster –One of the Largest Structures in the Universe



Enormous bright loops, ripples of doomed galaxies, and jet-like streaks are apparent in the central regions of the Perseus galaxy cluster sown above. The image reveals evidence of the turmoil that has wracked the cluster for hundreds of millions of years. One of the most massive objects in the universe, the cluster contains thousands of galaxies immersed in a vast cloud of multimillion degree gas with the mass equivalent of trillions of suns.

The dark blue filaments in the center are likely due to a galaxy that has been torn apart and is falling into NGC 1275, a.k.a. Perseus A, the giant galaxy that lies at the center of the cluster.

Special processing designed to bring out low and high pressure regions in the hot gas has uncovered huge low pressure regions (shown in purple in the accompanying image overlay, and outlined with the white contour). These low pressure regions appear as expanding plumes that extend outward 300,000 light years from the supermassive black hole in NGC 1275.

The hot gas pressure is assumed to be low in the plumes because unseen bubbles of high-energy particles have displaced the gas. The plumes are due to explosive venting from the vicinity of the supermassive black hole.

The venting produces sound waves which heat the gas throughout the inner regions of the cluster and prevent the gas from cooling and making stars at a high rate. This process has slowed the growth of one of the largest galaxies in the Universe. It provides a dramatic example of how a relatively tiny, but massive, black hole at the center of a galaxy can control the heating and cooling behavior of gas far beyond the confines of the galaxy.

A 53-hour Chandra observation shown below of the central region of the galaxy cluster has revealed wavelike features that appear to be sound waves. The features were discovered by using a special image-processing technique to bring out subtle changes in brightness.

These sound waves are thought to have been produced by explosive events occurring around a supermassive black hole (bright white spot) in Perseus A, the huge galaxy at the center of the cluster. The pitch of the sound waves translates into the note of B flat, 57 octaves below middle-C. This frequency is over a million billion times deeper than the limits of human hearing, so the sound is much too deep to be heard.

The image also shows two vast, bubble-shaped cavities, each about 50 thousand light years wide, extending away from the central supermassive black hole. These cavities, which are bright sources of radio waves, are not really empty, but filled with high-energy particles and magnetic fields. They push the hot X-ray emitting gas aside, creating sound waves that sweep across hundreds of thousands of light years.

The detection of intergalactic sound waves may solve the long-standing mystery of why the hot gas in the central regions of the Perseus cluster has not cooled over the past ten billion years to form trillions of stars. As sounds waves move through gas, they are eventually absorbed and their energy is converted to heat. In this way, the sound waves from the supermassive black hole in Perseus A could keep the cluster gas hot.

The explosive activity occurring around the supermassive black hole is probably caused by large amounts of gas falling into it, perhaps from smaller galaxies that are being cannibalized by Perseus A. The dark blobs in the central region of the Chandra image may be fragments of such a doomed galaxy.



The Daily Galaxy via Chandra X-Ray Observatory

Image credit: NASA/CXC/IoA/A.Fabian et al.



"The Galaxy" in Your Inbox, Free, Daily