Sunday, August 19, 2007

What Broken Sound Looks Like

It's "gotta share" time.

When an airplane travels at a speed faster than sound, density waves of sound emitted by the plane cannot precede the plane, and so accumulate in a cone behind the plane. When this shock wave passes, a listener hears all at once the sound emitted over a longer period: a sonic boom. As a plane accelerates to just break the sound barrier, however, an unusual cloud might form. The origin of this cloud is still debated. A leading theory is that a drop in air pressure at the plane described by the Prandtl-Glauert Singularity occurs so that moist air condenses there to form water droplets. Above, an F/A-18 Hornet was photographed just as it broke the sound barrier.

I don't care what you call it, but it sure is cool.

1 comment:

Tully said...

That pic's been in my screensaver file for months. MASSIVE cool.