21. THE REASON OF ABSENCE OF THE ATMOSPHERE ON THE MOON

21. THE REASON OF ABSENCE OF THE ATMOSPHERE ON THE MOON

Our moon like the rest of the bodies in our solar system is an ejection of solar material. It was "captured" by the Earth and began to rotate around it. And it was formed around the same time as Earth. Therefore, it consists initially the same percentage of heavy elements, as in the composition of the earth – that is larger than in Venus and Mercury, but less than in the giant planets. Due to the larger number of chemical elements constituting the earth, the absolute number of heavy elements in its composition initially was more than that in the composition of the moon. Therefore, the processes of radioactive decay in the Earth proceed more intensively than in the bowels of the Moon. As a result, during the radioactive decay the Moon produces less light elements than Earth. This, and the fact that the number of elements of the Moon is less than the number of elements of the Earth and, consequently, the total gravity field is weaker causes that this small amount of gases that formed in the bowels of the moon is not held by the gravitational field.

But on many satellites of Jupiter, for example, on Io, the atmosphere exists. This is explained by the fact that the solar substance from which these satellites formed was rich in heavy elements (like substance of the giant planets themselves).