Forever hidden from Earth's observer, it has been shrouded in myths for centuries. The first photos, mysterious craters, and basaltic seas — what does the side we never see live by? The Moon has always been a close yet unreachable companion. But the far side of the Moon, hidden from human eyes by synchronous rotation, remained a symbol of the unknown until the mid-20th century. Today, we know more about this hemisphere than ever before — but it is still where the main mysteries of our natural satellite lie. ≈ 41%the surface of the Moon is never visible from Earth Why Can't We See It? The reason is the so-called synchronous (tidal) capture. The Moon orbits the Earth with the same period as it rotates around its own axis. The period of rotation coincides with the orbital period, so only one hemisphere is visible from Earth. The far side is always turned away from us. This is not a shadow, not eternal night — it receives just as much sunlight as the visible side. Just its rays never reach the observer on Earth. First Legends and Hypotheses Before the space era, the far side of the Moon was an absolute terra incognita. Some astronomers speculated that there might be an atmosphere, water, or even unknown forms of life there. Science fiction depicted pictures of lost lunar civilizations. It was only in 1959 that the Soviet automatic station "Luna-3" made a historic flyby and transmitted the first images. Humanity first saw what had been hidden for billions of years. October 7, 1959 — "Luna-3" took 29 photographs covering about 70% of the far side. The quality was low, but there was no doubt: the relief was completely different. The Main Difference: Thin Crust, Mountains, and Almost No Seas The first thing that amazed scientists was that there are almost no lunar seas on the far side, extensive dark areas filled with solidified basaltic lava. If on the visible side "oceans" and "seas" occupy about 31% of the surface, then on the far side their share is only 1–2%. ... Read more