The natural and only satellite of the Earth, the Moon,after the sun is the second object in brightness. In magnitude, it is the fifth object of the solar system. Between the centers of the Moon and the Earth, the average distance is 384467 km. The mass of the moon corresponds to a value of 7.33 * 1022kg.
Since ancient times, people have attempteddescribe and explain her movement. The basis of all modern calculations is the theory of Brown, which was created at the turn of the XIX - XX centuries. To determine the exact motion of this celestial body was necessary not only the mass of the moon. Numerous coefficients of trigonometric functions were taken into account. Modern science can perform more accurate calculations.
Laser location allows you to measure dimensionscelestial objects with an error of just a few centimeters. With its help, it was found that the mass of the moon is much less than the mass of our planet (81 times), and its radius is 37 times smaller. For a long time it was not possible to determine this value with accuracy, but the launch of space satellites made it possible to open new perspectives. An interesting fact is known that at the time of Newton the mass of the Moon was determined by the magnitude of the tide it caused.
We can see the illuminated surface in different ways.this companion. The visible part of the disk illuminated by the sun is called the phase. In total there are four phases: the completely dark surface of the moon - the new moon, the growing moon sickle - the first quarter, the fully illuminated disk - the full moon, the illuminated half from the second side - the last quarter. They are expressed in hundredths and tenths of a unit. The change of all lunar phases is a synodic period, which is the revolution of the moon from the new moon phase to the subsequent new moon. It is also called the synodic month, equal to about 29.5 days. During this period of time, the Moon will be able to go along an orbit and have time to go twice in the same phase. The sidereal period of circulation, lasting for 27.3 days, is the complete revolution of the moon around the earth.
The statement thatthe surface of the moon we see from one side and the fact that it does not rotate. The movements of the moon occur in the form of rotation around its axis and a revolution around the earth and the sun.
Full rotation around its own axis occursfor 27 Earth days 43 min. and 7 hours. The circulation in an elliptical orbit around the Earth (one complete revolution) takes place in the same time. This is influenced by tides in the lunar crust, causing tides on Earth, occurring under the influence of lunar attraction.
Being farther from the moon thanThe Earth, the Sun, because of its enormous mass, attracts the Moon twice as much as the Earth. Earth distorts the trajectory of the Moon around the Sun. In relation to the Sun, its trajectory is always concave.
The moon has no atmosphere, the sky above it is alwaysblack Due to the fact that sound waves do not propagate in a vacuum, there is utter silence on this planet. Under direct rays of the sun, the temperature during daytime is many times higher than the boiling point of water, and at night it reaches –150 С. The specific gravity of the moon is one. Its density is only 3.3 p. more water. On its surface there are huge plains, which are covered with frozen lava, a lot of craters formed during the fall of asteroids. The force of gravity is inferior to the gravity of the earth, and the weight of the moon is less than the Earth, so the weight of a person’s body can decrease 6 times while on the Moon.
For radioactive substances, scientists have identifiedthe approximate age of the moon, which is 4.65 billion years. According to the latest most plausible hypothesis, it is assumed that the formation of the moon occurred as a result of a gigantic collision with the young Earth of a huge celestial body. According to another theory, the Earth and the Moon were formed independently in completely different parts of the solar system.
