Lunar Capture

Origins of the Earth's Moon

Orbital Evidence

If there is one thing that most lunar scientists agree upon, it is that it is very difficult to explain how the current dynamical state of the Earth-Moon system evolved. Another way of looking at the situation is to say that the current system dynamics should have dampened out in a much shorter time frame than the age of the system. It is concluded that some outside “force” has maintained the system dynamics for the age of the system or that some outside “fore” has preterbed the system some time later in its evolution.

It is expected that the Moon should be orbiting the Earth’s equator and that the Earth should have a fairly vertical axis of rotation. In this scenario the Earth, Moon and Sun would all be moving in the same plain. This, however, is not the case. The Moon moves up and down relative to the Earth’s equator by nearly 11 degrees. The tilt of the Earth’s axis is about 22 1/2 degrees. This situation, it is thought, could not have persisted since the origin of the system.
Earth and Moon

Time Distance Dilemma

The present location of the Moon is approximately 240,000 mi. from Earth or 60 Earth radii (12). The Moon is retreating from the Earth at approximately 1.5 inches per year and accelerating (13). The understood lifetime of the Earth-Moon system is assumed to be the age of the solar system or on the order of 4-4.5 billion years.

The problem is basically this: if the Moon originated at the Roche limit, which is the inner most place upon which it is agreed that the Moon could have formed at the beginning of the solar system, and its current rate of retreat is projected backward, then the Moon is too close. “Unless present estimates of acceleration are vastly in error only a veritable energy sink can solve the time scale problem (14).” This is a time problem; just too much time has passed for the Moon to still be so close.

To make matters worse, there is an observable excess of angular momentum in the Earth-Moon system and it seems clear that some extra energy has somehow been introduced into the system.

Angular Momentum

The angular momentum of the Earth-Moon system is a one-of-a-kind in our solar system. The Moon’s motion does not fit the fundamental laws of the universe. With the Earth-Moon system, the Moon is actually retreating from the Earth and its retreat is accelerating. It was the natural philosopher Kant in 1754 who first hypothesized that the Moon must be retreating from the Earth. Apollo missions some two hundred years later proved this hypothesis. It is not that the Moon is retreating that is unusual but that it appears to be retreating at an unusual rate.

A Close Approach Lunar Model explains this “excess of momentum” by a simple method. The Moon is not on its original orbital path. The Moon is currently in a retreating from an intermediate regression of its original orbit.

Did you know?

By placing a mirror on the Moon and measuring the time it takes light to pass to and from the mirror, Apollo missions proved that the Moon is actually retreating.

Orbital Irregularities

The solar system is an incredibly precise place and the orbital state of the planets and regular satellites are extremely constant. The outer planets locations were predicted, prior to their discoveries, from the slightest wobble detected in the orbits of the inner known planets. Yet in our own Earth-Moon system there is so much movement and wobble that we cannot even predict where our own planet will be in a few weeks (16).

The wobble of the Earth’s axis, part of which is understood and part of which defies prediction, is of major importance to science today. It causes a current technical problem for the maintaining of man-made satellites in their correct orbits. The unpredictable part of the wobble is known as Chandler’s wobble. A Close Approach Lunar Model is particularly good at explaining why these orbital irregularities exist. The know non-equatorial orbit of the Moon places torques on the Earth which lead to the axial tilt of the Earth.