Christmas Post # 4

This post isn't super deep but this Christmastime quasi-mathmatical proof sure made me laugh, especially hearing my friend Beth read it outloud the other day. As a effort to create a little moment of personal theatre in your own life you could try reading it out loud too. Don't worry no one's watching. Give it a try. That is unless you're in a public space, like a cafe or something. Then everyone is watching. And waiting for you to perform.

In that case the choice is up to you, you can either order a round of peppermint mochas for everyone, stand on the nearest cafe table and belt it out for everyone's listening pleasure, you can wait until you're in the privacy of your own home and read it in a whispered, lips barely moving "I'm not really reading this outloud" voice, or best of all you can find a trusted friend or group of friends and share it with them as a controlled explosion of lighthearted holiday frivolity. The choice is yours. Enjoy!

Santa Claus: An Engineer's Perspective

I. No known species of reindeer can fly. However, there are some 300,000 species of living organisms yet to be classified. While most of these are insects and germs, this does not completely rule out flying reindeer (which only Santa has ever seen).

II. There are approximately two billion children (persons under 18) in the world. However, since Santa does not visit children of Muslim, Hindu, Jewish or Buddhist religions, this reduces the workload for Christmas night to 15% of the total, or 378 million (according to the Population Reference Bureau). At an average (census) rate of 3.5 children per house hold, that comes to 108 million homes, presuming that there is at least one good child in each.

III. Santa has about 31 hours of Christmas to work with, thanks to the different time zones and the rotation of the earth, assuming he travels east to west (which seems logical). This works out to 967.7 visits per second. This is to say that for each Christian household with a good child, Santa has around 1/1000th of a second to park the sleigh, hop out, jump down the chimney, fill the stockings, distribute the remaining presents under the tree, eat whatever snacks have been left for him, get back up the chimney, jump into the sleigh and get on to the next house.

Assuming that each of these 108 million stops is evenly distributed around the earth (which, of course, we know to be false, but will accept for the purposes of our calculations), we are now talking about 0.78 miles per household; a total trip of 75.5 million miles, not counting bathroom stops or breaks. This means Santa's sleigh is moving at 650 miles per second---3,000 times the speed of sound. For purposes of comparison, the fastest man-made vehicle, the Ulysses space probe, moves at a poky 27.4 miles per second, and a conventional reindeer can run (at best) 15 miles per hour.

IV. The payload of the sleigh adds another interesting element. Assuming that each child gets nothing more than a medium sized Lego set (two pounds), the sleigh is carrying over 500 thousand tons, not counting Santa who is invariably described as overweight. On land, a conventional reindeer can pull no more than 300 pounds. Even granting that the "flying" reindeer could pull ten times the normal amount, the job can't be done with eight or even nine of them. Santa would need 360,000 of them. This increases the payload, not counting the weight of the sleigh, another 54,000 tons, or roughly seven times the weight of the Queen Elizabeth (the ship, not the monarch).

V. 600,000 tons traveling at 650 miles per second crates enormous air resistance --- this would heat up the reindeer in the same fashion as a spacecraft re-entering the earth's atmosphere. The lead pair of reindeer would absorb 14.3 quintillion joules of energy per second each. In short, they would burst into flames almost instantaneously, exposing the reindeer behind them and creating deafening sonic booms in their wake. The entire reindeer team would be vaporized within 4.26 thousandths of a second. Santa, meanwhile, would be subjected to centrifugal forces 17,500 times greater than gravity. A 250 pound Santa (which seems ludicrously slim) would be pinned to the back of the sleigh by 4,315,015 pounds of force.

VI. In conclusion, if Santa ever did deliver presents to all the good childern on Christmas eve...HE'S DEAD NOW!