Stars In A Jar -- Sonoluminescence
[11 June 2000]
06/11/00- NASHVILLE, TENNESSEE (McClure & Trowbridge Publishing)
Song Shopping Center - http://TrowbridgePlanetEarth.com/T2/T2C1.html
Think music has a divine effect on humans, animals, and plants? Maybe it does! Ordinary bubbles of air, in ordinary jars of water, produce a mysterious blue light and temperatures hotter than the sun's surface when bombarded with ultrasound! We see the light as continual even though it really is flashing on and off 30,000 times a second, just like we see a TV picture as continuous (even though it blinks at a far slower rate.)
So what's really going on with this blue light from air bubbles? Get ready... (deep breath... baby steps...) It's called sonoluminescence, and nuclear physicists Thomas Matula and William Moss are researching the phenomenon. Moss' wife saw mention of it in a magazine, circled it, and scribbled a note to William: "Huh? Why don't you look at this?". He is.
An air bubble in water instantaneously expands 1000 fold when subjected to ultrasound. There is a near vacuum inside the expanded bubble, with high pressures surrounding it. The bubble collapses, shrinking to less than 1/5'th of its original size, and the temperature shoots to "an estimated 10,000 degrees C to possibly more than a million degrees C - hotter than the surface of the sun." (Let's see... 100 degrees C is the boiling point of water, 0 degrees C is the freezing point of water, and the human body is almost totally water.)
This hyper-heat from the implosion (the inward collapse of the bubble) produces a tiny flash of blue light, which we see as a continuous light. The bubble continues expanding - collapsing - emitting blue light flashes - 30,000 times a second, as long as the ultrasound is going!
What started out as fusion weapons research is leading us toward applications like nuclear and toxic chemical waste disposal - safely, totally eliminating the hazards associated with such waste - and better chemistry and physics research tools.
[c.2000 Trowbridge Publishing]
[Ref. Pop.Sci. V253, No6; 88-91]