Mercury is Closer to the Sun, but Venus is Hotter

Venus is the hottest planet in our solar system, reaching temperatures of 864 degrees Fahrenheit (462 degrees Celsius). Even though Mercury is twice as close to the Sun, it doesn't have an atmosphere to trap heat, causing its temperature to plummet at night.

Venus is wrapped in a suffocating blanket of carbon dioxide so thick that the pressure on the surface is equivalent to being 3,000 feet underwater. This atmosphere acts like a one-way door, letting solar energy in but never letting the heat escape. This runaway greenhouse effect makes the surface hot enough to melt lead in seconds.

Because the atmosphere is so dense, the heat is distributed evenly across the entire planet. There is no relief at the poles and no cooling during the night. The temperature is identical everywhere, 24 hours a day, regardless of whether you are in the sun or the shade.

To make matters stranger, it rains sulfuric acid on Venus, but the surface is so hot that the rain evaporates before it ever hits the ground. The clouds are so reflective that they bounce 70% of sunlight back into space, which is why Venus glows so brightly in our night sky.

Even though it is nearly a twin to Earth in size, the winds on Venus are so fast they whip around the entire planet in just four Earth days.