Why does the sun set in the west?

There is an old saying in China: "The sun rises in the west". In people's common sense, it is impossible to say that the sun rises in the east and rises in the west. However, in one place, the sun really rises in the west and sets in the east day after day. This place is Venus, one of the eight planets in the solar system.

Venus

Venus is the second closest planet to the sun and the closest planet to the earth. At the same time, it is also a terrestrial planet. Because its mass is similar to that of the earth, it is sometimes called the "sister star" of the earth. The surface of Venus is somewhat similar to the surface of the earth. Because of the protection of the atmosphere, there are not as many craters on Venus as there are on Mercury and the Moon. The earth is relatively flat, but there are high mountains. The maximum height difference of Venus on the mountain is similar to that of the earth, and there are also tall volcanoes, extending to 300,000 square kilometers.

Most of the surface of Venus looks like the land of the earth. The land of the earth only accounts for 3/ 10 of the surface area, and the remaining 7/ 10 is a vast ocean. Venus occupies 5/6 of its surface area, and the remaining 1/6 is a small waterless lowland-so far no water has been found on the surface of Venus.

Venus surface-Soviet probe shooting

But why does the sun on Venus rise in the west and set in the east? When scientists used radar to detect the surface of Venus, they found that Venus is the only planet in the solar system that rotates in the opposite direction, that is, its rotation and revolution are opposite. Therefore, the sun on the earth, which rises in the east and sets in the west, completely changed its direction when it reached Venus, and became a rising sun in the west and setting in the east.

Imaginary map of Venus surface

At the same time, it is also known that Venus rotates very slowly, once every 243 days. If we look at the stars on Venus, we can only see the same map in space every 243 days. If the rotation period of Venus is measured based on the sun, there are only 1 16.8 Earth days. Venus can see two sunrises and sunsets in one rotation because it runs a long distance along the orbit of revolution during this period. So a Venus day is 1 16.8 Earth days, and a day on Venus is equal to 1 16 days on earth!