Blog vol 2. 33. Rudolph the Yellow-Nosed Reindeer??
On Dasher and Dancer and Prancer and Vixen…. the start of the ode to Rudolph is known by all, especially, at this time of year. Did you ever wonder whether his red nose really worked on all those Christmas Eves? It was on that foggy Christmas Eve so many years ago that Santa had the bright idea to have Rudolph lead his sleigh through all that pea-soup. Are there not better colours for helping with fog than red? After all most fog lights we have for cars today are one of two colours, yellow or amber, not red. Rudolph the yellow-nosed reindeer? it could work. Who is right?
So I took off my night cap and donned my thinking cap. Maybe, it is the wavelength of the light that makes yellow better, with yellow in the 570-590 nanometre range and red being quite a bit longer at 620-750. Some have thought that the shorter wavelength helps to penetrate the small water droplets present in fog, but there is no credence to this theory. The water droplets are a lot larger than the wavelength of either yellow or red, so wavelength makes very little difference. The most likely explanation is that the vast majority of our cone receptors are more sensitive to the yellow wavelength than the red.
But Santa cannot be stupid (we can all agree on this point, since I still am hoping for a big haul on Santa’s big night). On goes the thinking cap again, and the answer is plain to see. The red colour works with Santa’s dark adaptation at night so he can see to land the sleigh and find your house and your chimney. We all know that as we get older it takes longer to dark adapt, and guess how old Santa is, of course, then red for dark adaptation. Everybody knows that Santa is very clever (here’s hoping), so even the designers of airplanes and towers and skyscrapers also use red light as a beacon to make sure that nobody collides with them.
So what can we conclude from this, besides Santa being extremely astute and bright? We should stick to yellow or amber for our fog lights and leave the flying and sleighing to Santa with Rudolph and his very bright red proboscis leading the way.
Merry Christmas to all, and to all, a good night,
the good doctor, Dr. Mark Germain, Burlington Optometrist
