May 20, 2022

The Moon (lat. Moon) is the Earth's natural satellite and also the closest celestial body, 384,401 km away on average, so that light from the Moon reaches the Earth in 1.25 seconds. The Moon orbits the Earth on an elliptical path at an average speed of 1.02 km / s, and crosses a daily arc of 13 ° 10 ". The Moon is a solid celestial body with a diameter of 3,647 km, and is 14 times in area, 50 times in circumference mass 81 times less than the Earth.The acceleration of gravity is 6 times less on the Moon than on the Earth.The Moon orbits the Earth in 27 days 7 hours 43 minutes and 11.6 seconds (sidereal month). The moon is the brightest celestial body after the sun, whose light is reflected (it does not create its own light like stars). The full Moon is of apparent magnitude -12.74, its albedo is 0.07, and its angular magnitude is seen at an angle of approximately 0.5 °. It constantly turns the Earth on the same side, because the orbit and rotation take place in the same direction, and the times of orbit and turn are the same, which is a consequence of the Earth's tidal influence. Its path is inclined towards the plane of the ecliptic by 5 ° 9 '. More than half of the Moon's surface is visible due to libration (59%). Lunar changes are the luminosity of the Moon during the synodic month (new moon, first quarter, full moon and last or last quarter), and they occur due to the constant change of the Moon's position towards the Earth and the Sun. When the Moon enters the Earth's shadow, an eclipse of the Moon occurs, and when it is between the Earth and the Sun (Moon's nodes), an eclipse of the Sun occurs. The attractive forces of the Moon and the Sun cause sea tides on Earth. With its attractiveness, the Moon influences the Earth's path around the Sun (nutation). The density of the Moon is 3.34 t / m3, making it the second natural satellite in the solar system. Its movement in the complex gravitational field of the Earth and the Sun is subject to numerous disturbances. The distance of the Moon from the Earth is constantly changing, because the Moon orbits the Earth in an ellipse, and besides, in longer time intervals, its path does not have a constant shape and size. The average distance is 384,401 km, which was first accurately measured by the daily parallax method, then by radar and lidar. The motion of the Moon in the complex gravitational field of the Sun, Earth and planets is processed by the methods of celestial mechanics. For the period from 1750 to 2125, it was calculated that the Moon closest to the Earth, 356,375 km, was on January 4, 1912, and that the farthest from the Earth, 406,720 km, would be