Those who observe the Moon from Earth may notice that the satellite, passing through its orbit, always turns to its planet by the same side. A logical question arises: does the moon rotate or is it motionless about its axis? Despite the fact that our eyes say “no”, scientists say the opposite - the moon does rotate.
The period of the Moon's revolution around the Earth is 27.322 days. It takes the satellite approximately 27 days to make one revolution around its own axis. That is why for observers from the Earth the illusion is created that the Moon remains absolutely motionless. Scientists call this situation synchronous rotation.
However, it is worth paying attention to the fact that the Moon's orbit does not completely coincide with its rotation axis. The moon travels around the earth in an elliptical orbit, a slightly elongated circle. When the Moon approaches the Earth as far as possible, it rotates more slowly, which allows us to see the usually hidden 8 degrees on the eastern side of the satellite. When the Moon is at its maximum distance, the rotation is faster, so an additional 8 degrees can be seen on the west side.
It should be noted that the far side of the moon is visually very different from how we are used to seeing it from Earth. If the moon's near side is mostly made up of lunar seas - large dark plains created by solidified lava flows - and low lunar hills, then the moon's back is literally dotted with craters.
Meanwhile, scientists say that the moon's rotation period was not always equal to its orbital period. In the same way that the gravity of the moon affects the ocean tides on Earth, the gravity of the earth also affects the moon. But since there is no ocean on the planet's natural satellite, the Earth acts directly on the surface of the Moon, creating tidal bulges on it along the line pointing to the Earth. Tidal friction gradually slows down the moon's rotation.
The satellite itself has the same effect on Earth, so every 100 years the length of the day increases by a few milliseconds. So, during the dinosaurs, the Earth made one revolution around its axis in 23 hours. Nowadays, 24 hours (or 86,400 standard seconds) per revolution around its axis took the Earth in 1820. Since then, the planet's sunny day has increased by about 2.5 milliseconds.