Letter: Supersonic Santa

Letter: Supersonic Santa

Sir: Does Santa Claus exist?

There are perhaps 378 million Christian children in the world. At an average rate of 3.5 children per household, that comes to 108 million homes, presuming that there is at least one good child in each.

Santa has about 31 hours of Christmas to work with, thanks to the different time zones. This works out to 967.7 visits per second. So Santa has around a thousandth 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, Santa's sleigh is moving at 650 miles per second.

Assuming that each child gets nothing more than a medium-sized Lego set (two pounds), the sleigh is carrying over 500,000 tons. A conventional reindeer can pull no more than 300 pounds. Even granting that the flying reindeer could pull ten times the normal amount, Santa would need 360,000 of them. This increases the payload, not counting the weight of the sleigh, another 54,000 tons.

A 600,000-ton vehicle travelling at 650 miles per second creates 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. They would burst into flames almost instantaneously. The entire team would be vaporized within 4.26 thousandths of a second, or about the time Santa reached the fifth house.

D J R POWELL

Atomic Weapons Establishment