The moon is the only satellite of the Earth. The first person to explore it was Galileo. The same scientist also owns the first discoveries regarding the Earth's satellite: its approximate dimensions, craters and valleys on the surface. Now everyone can make Galileo's discoveries simply by using binoculars.
The moon and the planets of the solar system: comparison
The volume of the Moon is 21.99109 km3. Its mass is 7.351022kg. Knowing these values, it is possible to compare the sizes of the Moon and the Earth. The volume of the Earth is 10.83211011 km3. Its mass is 5.97261024 kg. Thus, the volume of the Moon is 0.020 of the volume of the Earth, and the mass is 0.0123. You can also compare the size of the Moon and Mars. The volume of the red planet is 6.0831010 km, mass is 3.330221023 kg. Therefore, Mars is approximately twice as large.
The moon differs in many ways from other satellites of the planets of the solar system, not only in size, but also in other parameters. It is believed that the "moons" of other planets could be formed as a result of one of two processes. The first way is to collect them fromdistributed dust and gas and further attraction to the planet by its gravitational field. The second way - other satellites of the planets of our system could simply be celestial bodies passing by, accidentally falling into the field of attraction. Scientists believe that this is how Mars got two satellites called Deimos and Phobos.
How was the Moon formed?
But the characteristics of the moon cannot 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 were formed, which rushed through space. And one of these celestial bodies collided with the Earth. Several fragments of the Earth were thrown into the surrounding space. Some of them gradually began to be attracted and formed the Moon.
Moon compared to moons of other planets
The moon is a fairly large satellite. It is surpassed in size only by such satellites of other planets as Io, Callisto, Ganymede, Titan. Thus, the size of the Moon allows this celestial body to occupy fifth place among the 91 satellites of the entire solar system.
The shape of the moon and its surface
The lunar surface undergoes very little change. After all, the era of active meteor showers remained for her in the distant past. Neither tectonic nor volcanic activity is observed on the surface of the Earth's satellite. The moon does not have a dense atmosphere and water, which alsoare two more reasons why the lunar form remains unchanged for man. Continental areas on the surface of the moon are distinguished by a lighter color. They have a large number of craters. It used to be thought that they could be of volcanic origin, but now the meteorite theory has taken over. Mountains, crevices, gorges were found on the Moon.
Mountain mountains are called the same as the terrestrial ones. 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 governs human emotions and the weather on Earth. For example, on a satellite map you can see the Sea of Tranquility, Crises, Rains, Clarity, as well as the Ocean of Storms.
Amazing coincidences
Scientists have discovered many amazing coincidences in the structure of the solar system. One of them is the following: between the Earth and the Moon, you can fit all the other planets of the system. The distance from the satellite to the Earth is about 384,400 km. In other words, the Moon is not that far from the Earth. NASA specialists decided to figuratively "push" all the remaining planets into the gap between the Moon and the Earth. To the surprise of the astronomers, they fit in there almost exactly, with only small gaps.
Now scientists can only guess whether this fact is a coincidence or not. In addition, this wonderful case is not the only one. The size of the Moon is selected in a very special way, and the distance from the Sun, it would seem, is measured to within a centimeter. After all, if the moon isbetween the Earth and the Sun, then it completely blocks it. This is how a solar eclipse happens. If the size of the moon were a little larger or, conversely, smaller, people would not be able to observe this amazing natural phenomenon.
Angular size of the Moon
This is simply her apparent size from the surface of the Earth. For example, the angular size of the satellite of our planet and the Sun is approximately the same, because it seems to people that these celestial 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 approximately 400 times larger than the Earth's satellite. But the Moon is 400 times closer to the Earth than the Sun. The radius of the luminary 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 when taking into account the fact 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 almost the same.
Moon and life on Earth
The moon has not only changed the appearance of the starry sky for the inhabitants of the Earth. This celestial body also made the appearance of life on our planet the most likely. The fact is that each planet oscillates during rotation, because of this, on other planets, the climate is constantly subject to change. With any unstable climate of emerging life, it is very difficult to gain a foothold on a celestial body. The size of the moon is not so small that it does not affect the climate. The moon contributes to the fact that the vibrations of the Earth during its rotation are softened.
