If we study rotations in space, then we need to know about two types: axial and around another more massive object (orbital). In the specific case, we are interested in the axial rotation of Venus, because it is the only (also Uranus, but it lies on its side) planet of the Solar System, which rotates around the axis in the opposite direction. Why?
How did the “rules” of rotation
The universe seems chaotic, so it’s not quite clear where all these rules come from. Why do planets rotate clockwise? The fact is that the foundation was laid at the time of the formation of the solar system. Do not forget that all objects are subject to solar influence.
Initially, there was a scale disk made of dust and gas (this material became the basis for the appearance of planets, asteroids, etc.). It rotated clockwise, and this trend passed on to all the planets that appeared here. That is, it is normal state. Then what is wrong with Venus, who chose the opposite rotation?
Scientists research question
This type of rotation (in the opposite direction) is called retrograde, and the planet is retrograde. Researchers began to study the planet in the last century. At first it was thought that life could be on it, because the surface was hidden behind a dense atmospheric layer. But the heat and acid rain became a major disappointment. However, there was a mysterious rotation. Venus rotates at a tilt at 177.36 ° from east to west. To be honest, it is still difficult for scientists to find the exact answer, but there are hypotheses.
This is one of the earliest assumptions. In 1965 it was actively promoted by several astronomers. The fact is that even in the early period of development a large cosmic rock crashed into the planet. The blow was so powerful that Venus began to rotate in the opposite direction. However, the theory did not pass the mathematical test, because the required size of the asteroid was simply to destroy the planet.
Planet turned up
In 1970 it was suggested that the planet initially rotated in the opposite direction. Just at a certain historical moment Venus turned over. But how to explain this phenomenon? Here the theorists are lost. After all, it’s not so easy to turn the whole world upside down. Although some believe that the blame is the Sun (powerful gravitational tides).
The role of the atmosphere
Despite the hellish conditions, Venus is able to boast a dense atmospheric layer. In this case, the mass of the planet itself is inferior to the earth. Perhaps the atmosphere squeezes Venus and rotates it the other way. This could also explain the slowness of rotation.
The hiding is hidden inside
The internal structure of Venus: the crust, the mantle and the core
The planet, like the rest, is represented by the core, the mantle and the crust. There is a possibility that friction between the crust and the mantle, together with tidal oscillations (the interaction of the atmosphere and the Sun) formed a torque. He kind of knocked the planet off balance, and she turned over. But this is possible only under the condition that it initially rotated at an angle of 90 degrees.
This is a very interesting hypothesis. Perhaps Mercury was previously not a planet, but a satellite of Venus! For some reason, a collision occurred, after which the planet began to rotate in the other direction, and Mercury lost most of the upper layer, and its orbit bent.
Some believe that this process was slow and natural. But so far no one knows the exact answer. It is important to take into account many factors, such as distance to the Sun, the density of the atmosphere, the angle of inclination, etc. Scientists do not give up and one day they will find a solution. What do you think?