In celebration, go check out the excellent Wikipedia page on the Doppler Effect, including one of my favorite Physics equations (while I wasn’t failing.) And if the idea isn’t sinking in, there are plenty of online demonstrations of why this effect occurs. (Science aside, I also recommend celebrating by imitating the sound of an English police car driving by in a movie. It works best if you simultaneously run by your significant other at high speeds.)

Because light can be a wave as well as a particle, the Doppler effect applies to light as well as sound. An increase in the observed wavelength of light emanating from a star is called a redshift. The principle is the same: as the source gets further from you, the wavelength (what it sound we perceive as pitch) shifts; in the case of a star, that translates to observed color.

Here’s the mind-bending caveat: there’s a misconception that Doppler-like redshifts are what allow astrophysicists to measure the expansion of the universe. Wrong! Why? Because it’s not the stars moving away from you (a la the Doppler ambulance); it’s the intervening space stretching, as per the understanding of General Relativity. There you go; if that hasn’t convinced you to go have a drink in honor of Christian Doppler, nothing will. (Heck, it’d probably convince him to have a few drinks, were he alive.)

Back to digital audio: If you want to reproduce the Doppler effect accurately, GRM Tools Classic has one of the best Doppler plug-ins I know of, available for both Pro Tools (RTAS/TDM) and VST. See the detailed review from Electronic Musician of a few years ago. GRM Tools is a great collection of plug-ins, but if you’re on Windows you can also opt for the much-cheaper GBP 15 a la carte option, Spacestation (VST). (Thanks, Afro!)

Or just go have that Dopplertini. (Anyone got a good recipe? I think it involves throwing the drink at high velocity . . .)

How will you spend the holiday? I’m thinking a screening of the brilliant Theremin documentary is in order here at CDM HQ. Or I could set off the building fire alarm with 109 candles.