Why is the temperature of Venus the highest in planets of the solar system?

Venus is the second farthest object from the sun in the solar system, only farther than Mercury.

Then Venus is hotter than other planets because it is close to the sun. But the question is why mercury, which is closer to the sun, is not as hot as Venus. This is because Venus has a thick carbon dioxide atmosphere on its surface. This kind of atmosphere has the function of heat preservation, that is, the "greenhouse effect" that people often say, which can make the temperature accumulate and not be easily emitted. Although it is farther away from the sun than mercury, the temperature is not easy to give off.

There is almost no atmosphere on the surface of mercury, and the heat absorbed will soon dissipate. At night, the surface temperature of Mercury is as low as-170 degrees Celsius, which is caused by the lack of atmospheric insulation.

Therefore, Venus has become the hottest planet in the solar system.