The Physics of Santa Claus - Rebuttal 5

Rebuttal 5
Lorenzo Sadun

I wrote this rebuttal to the "physics of Santa" analysis back in 1993:

If you're going to criticise Santa Claus on physical grounds, you may at least do it right.

The payload calculations are nonsense. Adding, say, 1000 stops back at the North Pole for reloading adds only a few percent to the entire distance covered, while reducing the payload by a factor of 1000. This is clearly the way to go.

The nonuniform distribution of children has a tremendous effect on the routing. With sensible routing, the average distance from a good child to the next good child is only a couple hundred feet in suburban conditions (this is clearly higher in the country, but is much less in, say, New York City). With only .05 miles between average good children, Santa need only travel at Mach 200, just a little faster than Ulysses. This reduces the force of air resistance by a factor of 200, and the power absorbed by the reindeer by 3000.

(Of course, if Santa stops to give coal to bad children it could slow things down a bit. But it appears that increasing population has made Santa give up that trick. When was the last time you heard of anybody getting a lump of coal?)

We all saw the pictures of a smart bomb falling through an Iraqi smokestack during the Gulf War. Clearly Santa uses the same technology for toys and chimneys. By dropping, say, 100 toys at a time from high altitude, Santa can reduce his speed by another factor of 10. While still supersonic, this is now slightly less than orbital velocity, sparing Santa and his team the trauma of extreme centrifugal force.

Santa's trip IS a remarkable feat of aeronautics, but please don't say it's impossible.