Which planet is the hottest in the solar system?

Venus is the hottest planet in the solar system primarily due to its thick atmosphere, which is composed mainly of carbon dioxide, with clouds of sulfuric acid. This dense atmosphere creates an intense greenhouse effect that traps heat and raises the surface temperature to extreme levels, averaging around 467 degrees Celsius (872 degrees Fahrenheit).

Even though Mercury is closer to the Sun, its thin atmosphere cannot retain heat, causing substantial temperature fluctuations that can drop to extremely low levels at night. In contrast, Venus maintains its high temperatures both day and night because the greenhouse gases prevent heat from escaping into space.

This combination of proximity to the Sun, atmospheric composition, and the resultant greenhouse effect makes Venus the hottest planet, surpassing the temperatures experienced on Mercury and the other terrestrial planets, including Earth and Mars.