Does the moon contain normal gravity?

TIDE : The moon affects the seas more than humans

The tides are an indisputable long-range action of the moon. They are essentially due to its gravitational force. This force depends on the one hand on the mass, but much more on the distance: the closer the moon is to the earth, the stronger it is. Everything that is on the moon-facing side of our planet is particularly strongly drawn to it. And not just the water.

The whole Earth's crust bulges around 30 centimeters towards the celestial body. However, the rocks are relatively rigid and do not cope with the movement forced by the force of attraction as well as the easily deformable water. That comes a little closer to the moon: A flood mountain is created.

The opposite side of the earth is further away from the moon, so the gravitational force is lower. Another factor dominates there, indolence. The earth's crust and the water on the opposite side “resist” the movement towards the moon, creating a second flood mountain. According to the laws of mechanics, it is seven percent lower than the bump on the side near the moon.

This is hardly noticeable in practice. Both mountains would not even tower half a meter high on an earth covered exclusively by water. This shows that the term “mountain” is unrestrainedly exaggerated. With an earth radius of almost 6400 kilometers, the change in altitude caused by the moon is tiny.

That on the coasts partly a Tidal range of more than ten meters is measured has several reasons. Initially, the flood mountains are not stationary. They are based on the moon, which orbits the earth once within 27.3 days. However, the earth's own rotation is much faster (24 hours per revolution), so that the surface under the flood mountains rotates away. Every coastal town experiences two high tides and two low tides within 24 hours and 50 minutes.

The actual change in water level depends on the shape of the seabed and the coastline. For example, if the flood mountain presses into a narrow river mouth, the water is literally piled up.

Even the high tide mountains vary in height, as not only the moon's gravity tugs at the earth, but also that of the sun. But because it is much further away, it is hers Influence only half as big.

In relation to a single person, the power of the moon is very small. The astronomer George Abell calculated it once. So that is Gravitational force of a mosquitothat sits on a man's arm, larger than that of the distant moon. nes

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