After my abstract on fat-bottomed girls and the rockin’ world had been posted for a while, a high school friend of mine, Chris Snook, sent me the following advisory:
Jon —
Ellen sent me the link to your abstract on fat-bottomed girls, and I felt compelled to point out a critical omission, namely the failure to account for tidal locking.
Tidal locking is the phenomenon whereby the moon’s tidal forces on the earth slow the rotation of both bodies and convert this kinetic energy into potential energy, pushing them further apart, currently at a rate somewhere around an inch a year. The first tidal lock was the cessation of the moon’s rotation relative to earth, which is why one side of the moon is invisible from earth. The second tidal lock is the cessation of earth’s rotation, which will occur when the moon is far enough away that it orbits the earth about every 46 days (I believe, it’s been a while since I did the calculations), instead of the current 28 days. When that happens, the earth’s day will be 46 times as long, and the moon will be permanently invisible to one half of the planet. Of course, that will require the moon being 1.4 times as far away from the earth as it is now, and at an inch a year the sun will burn out before this happens, barring a change in the rate it happens. (Actually, the rate changes as the moon gets further away, but not significantly in the next 5 billion years.)
While it is certainly true that fat-bottomed girls do not by themselves make the rockin’ world go ’round, removal of them could cause tidal locking to accelerate. Obviously, if we simply launch them beyond earth orbit, our planet’s mass will decrease and we will be more vulnerable to tidal locking.
If we launch them at great speed at a slight angle, retrograde to earth’s rotation, the reflex force would compensate for many years of tidal locking, but this strategy would require sending up a number of fat-bottomed girls that increases quadratically over time (actually worse than quadratic, as the earth’s mass starts decresing noticeably.) Obviously this rate of production of fat-bottomed girls is unsustainable with earth’s natural resources.
Alternatively, we could simply launch them into orbit. Even most high earth orbits would eventually decay, due to solar wind and various other factors. The only way to be sure to keep them up is to have them gravitationally coupled with the moon, which, because of tidal locking, isn’t falling on us.
Obviously, sending them to the moon just makes the problem worse, and Lagrange points L1, L2, and L3, which are along the line between the earth and the moon, which makes the tidal problem worse and is only metastable anyway. Lagrange points L4 and L5, which lead and trail the moon by 60 degrees respectively, are truly stable. If we launch them to only one of these points, they would cancel out more tidal force than they’d create, but only until they became a substantial fraction of the moon’s mass, at which point the problem gets worse. By sending them in equal proportions to both L4 and L5, they’d cancel out more lunar tidal force than they’d create until they completely overwhelm lunar tidal force. Of course, long before they exceed the moon’s mass by enough to cause this, they’d create new Lagrange points 60 degrees further away from the moon’s point in orbit. Once those collections gained sufficient mass, we could complete the hexagon and have 6 completely stable sattelites holding each other in orbit without exerting much tidal force (there’d still be some) on the earth. This would actually preserve the revolution of our rockin’ world without requiring a further and increasing deployment of fat-bottomed girls into orbit. In fact, we could stop at any point in the process and have a more stable orbital system than the one we started with.
So, it is true we can leverage fat-bottomed girls to preserve the rotation of our planet, but we must do it very carefully, as simply getting rid of them without thought will only make our problems worse.
Chris Snook, Copyright 2004, Some Rights Reserved. Reprinted under the terms set forth at http://creativecommons.org/licenses/by-sa/2.0/.