What is the sound of one black hole flapping?
NASA's Chandra X-ray observatory recently discovered a B-flat
flying through space at a wavelength 57 octaves below the middle
note of a piano -- the deepest tone ever detected. Scientists are
excited about this discovery because it potentially solves a
mystery about why gas surrounding the Perseus galaxy cluster does
not chill out as theory suggests it should. Since sound waves are
slower and more physical in nature than visible light or radio
waves, they physically compress air, water, or in this case,
interstellar gas as they move through it. Thus, the sound waves
heat gas as they move through it with an amount of energy
equivalent to the explosion of 100 million stars. This musical
production is in some sense no surprise to scientists; our own
solar system, and even Earth, put out their own symphony of
inaudible musical notes.
-- Joel Stonington