Venus is hot because it is surrounded by a very thick atmosphere which is about 100 times more massive than our atmosphere here on earth. As sunlight passes through the atmosphere, it heats up the surface of Venus. most of this heat cannot escape back into space because it is blocked by the very thick atmosphere of Venus. The heat because it is similar to how the glass in a greenhouse traps heat. The greenhouse effect on Venus causes the temperature at its surface to reach 864 degrees fahrenheit (462 degrees celsius), making Venus the hottest planet in our solar system.
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