Merry Christmas

After much research, we present the annual aeronautical engineers report on the theory of Santa:

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

There are two billion children (people under eighteen) in the world. But since Santa doesn't (appear to) handle the children belonging to Muslim, Hindu, Jewish and Buddhist religions, that reduces the workload to 15% of the total, or 378 million according to Population Reference Bureau. At an average (census) rate of 3.5 children per household, that's 108 million homes. One presumes that there's at least one good child in each.

Santa has 31 hours of Christmas to work with. This is due 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. That is to say that for each Christian household with good children, Santa has 0.0010334 second to park the sleigh, hop out of it, 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, since there are large areas in the earth which are completely uninhabited, such as the Pacific and Atlantic Oceans, but let's accept it for the purposes of our calculations), we are now talking about 1.255 kilometres per household, a total trip of 121.5 million kilometres; not counting stops to do what most of us do at lease once every 31 hours, like eating etc. Thus, Santa's sleigh must be moving at 1046 kilometres per second, 3000 times the speed of sound. For purposes of comparison, the fastest man-made vehicle on earth, the Ulysses space probe, moves at a pokey 44.1 kilometres per second. That's 158,760 kilometres per hour, by the way. Compared to most peoples' average driving speed (driving a car) of 80km/h, the Ulysses space probe would be 1984.5 times faster, and that's still not fast enough to catch up with Santa's sleigh. A conventional reindeer can run, at best, 24.1 kilometres per hour, by the way, 156,249 times slower than the speed at which Santa's sleigh had to run.

If every one of the 91.8 million homes with good children were to put out a single chocolate chip cookie and an 8 ounce glass of 2% milk, the total calories (needless to say other vitamins and minerals) would be approximately 225 calories (100 for the cookie, give or take, and 125 for the milk, give or take). Multiplying the number of calories per house by the number of homes, we get the total number of calories Santa consumes that night, which is 20,655,000,000 calories. To break it down further, 0.45 kilograms is equal to 3500 calories. Dividing our total number of calories by the number of calories in a kilogram and we get the number of kilograms Santa gains, 2,676,843 kilograms, which is 2950.7 tons.

The payload on the sleigh adds another interesting element. Assuming that each child gets nothing more than a medium-sized Lego set (0.91 kilograms), the sleigh is carrying 311,088,162 kilograms, not counting Santa, who is invariably described as overweight. On land, conventional reindeer can pull no more than 136.1 kilograms. Even granting that the "flying reindeer" can pull ten times the normal amount, we cannot do the job with eight, or even nine, reindeers. We need 252,200. This increases the payload - not counting the weight of the sleigh - another 48,987,976 kilograms. This is four times the weight of the Queen Elizabeth. The ship, not the monarch.

A mass of about 362,873,896 kilograms traveling at 1046.1 kilometres per second creates enormous air resistance. This will heat the reindeer up in the same fashion as a spacecraft re-entering the earth's atmosphere. The lead pair of reindeer will absorb 14,300,000,000,000,000,000 joules of energy. Per second. Each. For your information, an Olympic size swimming pool contains 2500m³ of water, and the density of water is approximately 1000kg/m³, so the mass of water in an Olympic size swimming pool would be 2,500,000kg. Knowing that the specific heat capacity of liquid water is 4181.3 J kg^-1 K^-1, the latent heat of vaporization of water is 2,272,000J/kg, and the specific heat capacity of water vapour is 2080 J kg^-1 K^-1, and applying all of the numbers into our calculations, 14,300,000,000,000,000,000 joules of energy will heat up the water in an Olympic size swimming pool from room temperature of 23 degrees Celsius, to become steam with a high temperature of 2,749,998,853 degrees Celsius. That's 2,749,999,126 K. Ah, let's just round it up to 2,750,000,000 K. For comparison, the temperature of the core of the Sun is estimated to be 15,710,000 K. So, the amount of energy generated per second would heat up the water in an Olympic size swimming pool to be steam 175 times hotter than the core of the Sun.

In short, the lead pair of reindeer will burst into flame almost instantaneously, exposing the reindeer behind them and creating deafening sonic booms in their wake. The entire reindeer team will be vaporized within 0.00426 seconds, which is right about the time Santa reaches the fifth house on his trip. Not that it matters, however, since Santa, as a result of accelerating from a dead stop to 1046.1 kilometres per second in 0.001 seconds, which is an acceleration of 1,046,100 kilometres per second squared, for your information, would be subjected to centrifugal forces 17,500 times greater than gravity. A 113.4 kilograms Santa, being very conservative in terms of guessing Santa's weight, would be pinned to the back of his sleigh by 1,957,258 kilograms (for your reference, just imagine 23,000 Alvins lying on top of you. Alvin is the fattest guy in my class 4R2 :P) of force. This will no doubt instantly crush his bones and organs, reducing him to a quivering blob of pink goo.

If Santa ever DID deliver presents on Christmas Eve, he's dead now.

A Merry Christmas to one and all!!