From the Discovery Channel:
Black Hole Sings Deepest NoteWouldn't Pythagoras (not to mention Plato, Ptolemy, and Boethius) be thrilled?
Sounds From The Perseus Cluster
Sept. 10, 2003 — For the first time ever, astronomers have detected sound waves coming from a massive black hole in space — and believe the discovery may help resolve a major mystery, the U.S. space agency NASA said Tuesday.
The Chandra X-ray Observatory had monitored for 53 hours noise coming from the central region of the Perseus galaxy cluster, according to NASA.
"We have observed the prodigious amounts of light and heat created by black holes, now we have detected the sound," said Andrew Fabian of the Institute of Astronomy (IoA) in Cambridge, England, and leader of the study.
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The pitch of the sound waves, equivalent to a B-flat — 57 octaves lower than a middle-C and at a frequency far deeper than the limits of human hearing — is the deepest note ever detected from an object in the universe, researchers said.
Bruce Margon, associate director at the Space Telescope Science Institute in Baltimore, Md., described the sound at a press conference here as being "a million, billion times deeper than the limits of human hearing."
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