Our natural satellite keeps running away from us!
4.5 billion years ago, the Moon circled our planet at a height of only thirty thousand kilometers. Today, it is fifteen or more times further and has been running away from us since primeval times!
The journey of the Moon into space continues today and will continue into the future. And all that is very interesting, but the question arises: why does the Moon move away in the first place?
The short answer is because the Moon attracts everything on Earth, especially the oceans, so a bulge appears on the surface which then pulls the Moon, accelerates it, and it climbs to a higher orbit around the Earth with acceleration!
But where does that bulge on the Earth that the Moon creates come from, and then it goes in front of the Moon-Earth line, and drags the Moon?
This is not a mere theoretical invention or a scientific assumption arising from mathematical models and computer simulations, but it has also been proven in practice.
So, apparently when Armstrong and Aldrin landed on the Moon in 1969, they placed a special laser mirror on its surface. When a laser is aimed at that mirror from Earth, the laser beam bounces off it and returns to Earth. Since we know the speed of light rays, one can calculate how far the mirror, or the Moon, is from us. Here is the formula:
Distance = (speed of light x time for the air to return) /2
which amounts to about 2.5 seconds, but it changes in accordance with the movement of the Moon in its elliptical orbit.
In fact, the exact calculation is much more complicated than the given formula shows, because it is necessary to take into account:
- the position of the Moon in the sky,
- the relative motion of the Earth and the Moon,
- the Earth’s rotation,
- the speed of light in different areas of the atmosphere, etc.
and at the same time, you should also know that the laser beam, no matter how narrow it seems to us, is scattered on the surface of the Moon for as much as 6.5 kilometers and that only a small part of it returns to Earth.
But finally, it was determined that our satellite is moving away from us today by 3.8 centimeters per year.
But how is it possible that the Moon makes a bulge that runs out in front of the Earth-Moon line and then pulls that same Moon forward and accelerates it, causing it to travel further and further away from us, while simultaneously slowing the Earth’s rotation and lengthening its day?
So, when a body orbiting the Earth reduces its speed, it slowly falls, i.e. is approaching us.
Like this: The Moon affects the entire planet with its gravity, but its effect is most noticeable on large bodies of water, such as the oceans. Therefore, the very ground on which we stand periodically rises (by about thirty centimeters), in accordance with the position of the Moon, but we will talk about water because its deformation is the most noticeable.
The Moon affects the tides and as it orbits the Earth, it draws water towards it and creates a bulge on the Earth’s surface. Therefore, the Moon draws large waters towards itself. But the Earth rotates much faster than the Moon orbits our planet.
It takes the Moon about 30 days to make one circle around the Earth, and during that time the Earth makes thirty rotations. Such a speed of rotation causes the tidal bulge to “run out”, rush and overtake the Earth-Moon line.
That bulge is, therefore, always in front of the Earth-Moon line and is strong enough to pull the Moon with its gravity, accelerate it and so the Moon moves away from us.
A similar thing happens between some other planets and their satellites, and even between close pairs of binary stars. The dynamics of tidal forces are widely present in the universe.
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