X-radiation From The Cluster
The detection of X-ray emission from Per XR-1 occurred during an Aerobee rocket flight on March 1, 1970, the source may be associated with NGC 1275 (Per A, 3C 84), and was reported in 1971. If the source is NGC 1275, Lx ~4 x 1045 ergs/s. More detailed observations from Uhuru confirmed the earlier detection and associated the source with the Perseus cluster. Per X-1 is the galaxy cluster at 4U 0316+41 designated the Perseus Cluster, Abell 426, and NGC 1275.
The galaxy cluster is the brightest cluster in the sky when observed in the X-ray band.
The cluster contains the radio source 3C 84 that is currently blowing bubbles of relativistic plasma into the core of the cluster. These are seen as holes in an X-ray image of the cluster, as they push away the X-ray emitting gas. They are known as radio bubbles, because they appear as emitters of radio waves due to the relativistic particles in the bubble. The galaxy NGC 1275 is located at the centre of the cluster, where the X-ray emission is brightest.
In 2003, astronomers detected the deepest note ever detected by mankind in the cosmos, a B♭, after 53 hours of Chandra observations. No human will actually hear the note, because its time period between oscillations is 9.6 million years, which is 57 octaves below the keys in the middle of a piano. The radio waves appear to be generated by the inflation of bubbles of relativistic plasma by the central active galactic nucleus in NGC 1275. They are visible as ripples in the X-ray band using Chandra X-ray Observatory, as the X-ray brightness of the intracluster medium that fills the cluster is strongly dependent on the density of the plasma.
Read more about this topic: Perseus Cluster
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