] The voice of a black hole is a deep, deep bass, 57
] octaves below middle C and far beyond the hearing range
] of humans. The Chandra X-ray Observatory has picked up
] sound waves for the first time from a cluster of galaxies
] 250 million light years away.
]
] Astronomers at the Institute of Astronomy in Cambridge,
] England, discovered the sound waves while analyzing the
] Chandra images of the Perseus cluster, an immense
] grouping of galaxies held in formation by the powerful
] tug of a supermassive black hole.

HoustonChronicle.com - Sound of black hole 57 octaves below middle C