The size of the moon, features, theory of origin and comparison with other celestial bodies of the solar system

The moon is the only satellite of the Earth. The first person who examined it was Galileo. This scientist also owns the first discoveries about the Earth satellite: its approximate dimensions, craters and valleys on the surface. Now the discoveries of Galileo can be done by everyone, simply using binoculars.

Moon and Planets of the Solar System: Comparison

The volume of the Moon is 21.99 * 10 ⁹ km ³ . Its weight is 7.35 * 10 ²² kg. Knowing these values, you can compare the dimensions of the Moon and the Earth. The volume of the Earth is 10.8321 * 10 ¹¹ km ³ . Its weight is 5,9726 * 10 ²⁴ kg. Thus, the volume of the Moon is 0.020 of the Earth's volume, and the mass is 0.0123. You can also compare the size of the Moon and Mars. The volume of the red planet is 6,083 * 10 ¹⁰ km, weight - 3,33022 * 10 ²³ kg. Consequently, Mars is approximately twice as large.

The moon in many respects differs from other satellites of planets of the Solar system not only in size, but also in other parameters. It is believed that the "moons" of other planets could have formed as a result of one of two processes. The first way is to collect them from distributed dust and gas and further attraction to the planet by its gravitational field. The second way - the other satellites of the planets of our system could simply be passing by heavenly bodies accidentally caught in the field of attraction. Scientists believe that this is how Mars had two satellites called Deimos and Phobos.

How did the Moon form?

But the characteristics of the moon can not be explained by these two options. Astronomers are sure that it appeared as a result of a powerful cataclysm in the solar system. As a result, a huge amount of space debris and young planets, which were worn in space, were formed. And one of such celestial bodies collided with the Earth. Several fragments of the Earth were thrown into the surrounding space. Some of them gradually began to attract and formed the Moon.

The moon compared with the satellites of other planets

The moon is a big companion. In size it is surpassed only by such satellites of other planets as Io, Callisto, Ganymede, Titan. Thus, the size of the moon allows us to occupy this celestial body among the 91 satellites of the entire solar system in fifth place.

The shape of the moon and its surface

The lunar surface is subject to very little change. After all, the era of active meteorite rains remained for her in the distant past. On the surface of the Earth's satellite there is also no tectonic or volcanic activity. The Moon does not have a dense atmosphere and water, which is also two more reasons why the lunar appearance remains unchanged for a person. The continental areas on the surface of the Moon are of a lighter color. They have a large number of craters. It used to be believed that they could have a volcanic origin, but now the theory of meteorites has gained the upper hand. On the Moon were found their own mountains, crevices, gorges.

The lunar mountains are called the same as the earthly mountains. Here you can see the Carpathians, and the Alps, and the Caucasus. Galileo also gave them such names. And the seas are named after the old belief that the Moon controls human emotions and weather on Earth. For example, on the map of the satellite you can see the sea of Tranquility, Crises, Rain, Clarity, and also the ocean of Storms.

Amazing coincidences

In the device of the solar system, scientists discovered many striking coincidences. One of them is the following: between the Earth and the Moon, you can fit all the other planets in the system. The distance from the satellite to the Earth is about 384,400 km. In other words, the Moon is not so far from the Earth. NASA specialists decided to "shove" all the remaining planets into the gap between the Moon and Earth. To the surprise of astronomers, they fit there almost exactly, with only small gaps.

Now scientists can only guess: is this fact a coincidence or not. In addition, this wonderful event is not the only one. The size of the moon is selected in a very special way, and the distance from the Sun would seem to have been measured to within a centimeter. After all, if the Moon is between the Earth and the Sun, it completely blocks it. So it turns out a solar eclipse. If the size of the Moon were slightly larger or, conversely, less, people could not observe this amazing natural phenomenon.

The angular dimension of the moon

This, simply, is its apparent size from the surface of the Earth. For example, the angular size of a satellite of our planet and the Sun is approximately the same, because people think that these heavenly bodies are equal. But in fact, the linear dimensions of the Moon and the Sun differ by almost 400 times. Here you can observe another amazing coincidence.

The sun is about 400 times larger than the Earth satellite. But the Moon is 400 times closer to the Earth than the Sun. The radius of the solar system is about 696 thousand km. The size of the moon, more precisely, its radius is 1737 km. This situation is unique in the entire solar system. This fact is especially surprising given that there are 8 planets and 166 satellites in the Solar System. As a result of this coincidence, the apparent size of the Moon and the Sun is practically the same.

Moon and life on Earth

The moon not only made the external appearance of the starry sky for the inhabitants of the Earth. This heavenly body also made the appearance of life on our planet the most probable. The fact is that each planet under oscillation makes fluctuations, because of this on other planets the climate is constantly subject to changes. With any unstable climate of the life that has arisen, it is very difficult to gain a foothold on the celestial body. The size of the moon is not so small as not to affect the climate. The moon contributes to the fact that the oscillations of the Earth when it rotates soften.