The Orbit of the Moon recedes from the Earth because of the gravitational pull of the Sun.
This computer model demonstrates the Sun's Gravity pulling the Moon away from a Planet.
In Reality the amount is a few millimetres per year.
This diagram was calculated precisely with Newton's: g=m/r^2

Click the link below and
Download Orbit Game 5 to see
how these images were generated:

>> orbit-game-5.exe <<
252 kb

<- See the Video (left)

. If your PC is set to use the comma as a decimal separator,
then these apps won't work so good.
Hello America!
The metric system is quite a good idea!

In this model the moon recedes from the Earth because of the Sun's gravity
and then drops into a lower orbit similar to Venus.
Here the Earth is in turquoise.

This diagram was calculated precisely with Newton's Gravitational Thereom.
This suggests that the Earth may have once been an outer moon of Jupiter.
The Sun will eventually capture all the moons and pull them to inner orbits.

In this model the moon moves away from the Earth due to the Sun's gravity
and then drops into a lower orbit.
As the Earth comes closer on its next orbit it re-captures the moon again.
After it is recaptured, the moon's orbit is much closer than before.
This is an extremely remote possibility.

This diagram was calculated precisely with Newtonian Gravity.

Download:

>> orbit-game-5.exe <<

252 kb
.

Another thought experiment springs to mind. It is the sort of reasoning that is so obvious in retrospect that I feel a bit embarrassed to say that I did not realize it before constructing the data model.

Imagine a universe that consists of just the Earth and the Moon. They have the same positions and momentums that they have in our universe; identical to ours except that Earth and Moon are alone without the Sun, stars or other planets. Now it surely must be clear that the moon will orbit the Earth quite happily and the Earth will exhibit a small fluctuation accordingly.

Now consider a second universe which in addition, also has the Sun in its regular position. Surely it is clear that the Sun will now drag at the Moon’s orbit, slowly pulling it away whereas in the first imaginary universe the Moon will not be pulled away? The Sun’s gravity just has to affect the moon. This is such clear proof that I can not consider any other theory about why the moon is receding to have any validity whatsoever.