More than other space objects since ancient times, the Moon has attracted man. Its reverse side, hidden from the earthly observer, gave rise to many fantasies and legends, was associated with everything mysterious and incomprehensible. Scientific study of the inaccessible part of the satellite began in 1959, when it was photographed by the Soviet Luna-3 station. Since then, data on the reverse side of the night star has increased significantly, but the number of questions related to it has decreased slightly.
Sync
Today, almost everyone knows what causes one of the main features that characterize the Moon. The reverse side of the satellite is hidden from an observer on Earth due to the synchronization of the movement of the night star around the axis and our planet. The time required for one revolution is the same in both cases. It should be noted that the reverse side of the satellite is illuminated by the Sun in exactly the same way as the visible side. The epithet "dark", often used to characterize this area of the Moon, is used rather in a figurative sense: "hidden", "unknown".
It is likely thatafter some time, the Earth will also be turned towards its satellite with only one of its parts. The mutual influence of two cosmic bodies can lead to complete synchronization. Pluto and Charon are examples of a system with such a coincidence of periods of motion - both bodies are constantly turned to the companion by the same side.
Librations
More than half of the moon's surface, approximately 59%, can be observed from our planet. This is explained by the so-called librations - the visible vibrations of the satellite. Their essence is that the orbit of the Moon around the planet is somewhat elongated. As a result, the speed of the object changes and libration in longitude occurs: a part of the surface alternately becomes visible to the earthly observer either in the east or in the west.
The inclination of the satellite axis also affects the increase in the area available for "viewing". It causes libration in latitude: the north and south poles of the moon become visible from the Earth.
Secrets of the Age: Far Side of the Moon
The study of the satellite with the help of spacecraft began in 1959. Then two Soviet stations reached the night luminary. "Luna-2" became the first apparatus in history to fly to the satellite (this happened on September 13, 1959). "Luna-3" photographed about half of the surface of the cosmic body, and two-thirds of the photographed fell on the reverse side. The data was transmitted to Earth. Thus began the study of the moon from the "dark", hidden side.
The first Soviet photographs were of rather poor qualitydue to the peculiarities of technical development at that time. However, they made it possible to see some of the nuances of the surface and give names to individual sections of the relief. The Soviet name of objects was recognized all over the world and fixed on the maps of the Moon.
Modern stage
Today the map of the far side of the moon is complete. One of the latest data on it was obtained by American astronomers in 2012. They noticed new geological formations on the surface hidden from the earth's observer, indicating a longer geological activity of the satellite than previously thought.
New space exploration of the moon is planned today. According to many astronomers, the satellite of our planet is a great place to host extraterrestrial bases in the future. Therefore, an accurate understanding of the features of the surface of the object is necessary. The study helps, in particular, to answer the question of where it is better to land a spacecraft: on the far side of the Moon or on its visible part.
Features
After a more detailed study of the part of the satellite hidden from observation, it became clear that its surface is in many ways different from the visible half. Huge dark spots that invariably adorn the face of the night luminary are a constant attribute that distinguishes the Moon visible from the Earth. The reverse side, however, has practically no such objects (in astronomy they are called seas). There are only two seas here - the Sea of Moscow and the Sea of Dreams, with a diameter of 275 and 218 kilometers, respectively. The most characteristic objectsfor the reverse side, these are craters. They are found on the entire surface of the satellite, but it is here that their concentration is greatest. Moreover, many of the largest craters are also located on the reverse side.
Giants
Among the most impressive objects on the far side of the satellite of our planet, a huge depression stands out. The basin, approximately 12 kilometers deep and 2,250 kilometers wide, is the largest such formation in the entire solar system. The dimensions of the Hertzsprung and Korolev craters are also striking. The diameter of the first one is almost 600 km, and the depth is 4 km. Korolev has fourteen smaller craters on its territory. Their sizes vary from 12 to 68 km in diameter. The radius of the crater Queen is 211.5 km.
The moon (the reverse side and the visible part), according to scientists, is a source of minerals that can be very useful to mankind in the future. Satellite studies are already therefore necessary. The moon is a real candidate for the location of extraterrestrial bases, scientific and industrial. In addition, due to its relative proximity, the satellite is a suitable object for practicing manned flight skills and testing technologies and engineering systems designed specifically for space exploration.
