[Audio: gong sound]
Our planet vibrates like a busy pipe organ. Earthquakes send sound waves bouncing through the entire planet. Volcanic explosions create sound waves, too, and so do the motions of molten rock below the surface, and even the sloshing of the tides.
One other source may set Earth to vibrating as well: tiny black holes.
Some models of the Big Bang say that these primordial black holes were created in the first moments of the universe. Matter and energy were so dense that they were easily squeezed tightly enough to form black holes that are smaller than an atom.
If these models are correct, then the universe may be filled with countless numbers of these tiny black holes.
They're so small that they could pass through a star or planet without hurting it. But they're massive enough that they could leave a signature: sound waves.
Last year, a team of scientists from Russia and Switzerland calculated that as it passed through Earth, a primordial black hole could generate as much energy as a small atomic bomb. But the energy would be spread across several hours and across a path that's thousands of miles long.
That wouldn't hurt our planet at all. But it should produce sound waves that ripple outward from the black hole's path. The right kind of detectors just might hear these ripples, and even trace their path through the planet -- the path of a tiny black hole.
Script by Damond Benningfield, Copyright 2009
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