Christmas from from an Engineer's Perspective (1 Viewer)

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1. 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 household, that
comes to 108 million homes, presuming that there is at least one good child
in each.

2. 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

This is to say that for each Christian household with a good child, Santa
has around 1/1000 of a second to park the sleigh, hop out, jump down the
chimney, fill the stockings, and 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.

3. 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

On land, a conventional reindeer can pull no more than 300 pounds. Even
granting that the 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).

4. 600,000 tons traveling at 650 miles per second creates enormous air
resistance -- this would heat up the reindeer in the same fashion as a
spacecraft reentering 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, or right about the time Santa reached the fifth house on his trip.
Not that it matters, however, since Santa, as a result of accelerating from
a dead stop to 650 mph in 0.001 seconds, would be subjected to centrifugal
forces of 17,500 g's. A 250 pound Santa (which seems ludicrously slim)
would be pinned to the back of the sleigh by 4,315,015 pounds of force,
instantly crushing his bones and organs and reducing him to a quivering
blob of pink-goo.

5. Therefore, if Santa did exist, he's now dead.
Poor Santa. Didn't even live till retirement.


Gold Member
Rumor has it that Santa has hired... OTHER SANTAS!!!!! And theres a whole farm of reindeer to act as his fleet....
You need a sixth clause (pun intended):
Santa can defy the laws of the universe as we know it.
Ya 6 santa's running around ought to do it. You can do the math.
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I'm glad you posted this, I was going to dig it out of my old files, but hadn't gotten around to it yet. Even though it's been around for years, it still makes me laugh.
Evo said:
I'm glad you posted this, I was going to dig it out of my old files, but hadn't gotten around to it yet. Even though it's been around for years, it still makes me laugh.
oooh someone doesn't read the PF blog! I'm telling


Jelfish said:
oooh someone doesn't read the PF blog! I'm telling
It's in the blog? Of course I read it there... This was just a test to see if "you" were reading. :redface:

Anyway, found the original source - Is There A Santa Claus? by Richard Waller
Originally published in Spy magazine, January 1990.

My link to great Santa stuff is dead. :cry:

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