Venus Is Hotter Than Mercury — Even Though Mercury Is Closer to the Sun
Answers: “why is venus hotter than mercury?”
Mercury orbits the Sun at about 58 million kilometers. Venus is nearly twice as far out, at 108 million. By every intuition, Mercury should be the furnace of the solar system.
It isn’t. Venus is.
The surface of Venus holds steady at around 465°C (870°F) — hot enough to melt lead — day and night, pole to equator. Mercury, despite sunbathing at half the distance, tops out around 430°C on its day side and plunges to roughly –180°C at night, because it has almost no atmosphere to hold the heat in.
That’s the secret: the atmosphere is everything.
Venus is wrapped in a crushing blanket of carbon dioxide about 90 times thicker than Earth’s atmosphere. Sunlight gets in, but the heat it generates cannot get back out — the CO₂ traps it, reflects it back down, and the planet cooks. Scientists call it a runaway greenhouse effect, and Venus is the textbook case of what happens when one goes unchecked.
There’s an eerie footnote to this. Some planetary scientists believe Venus may once have had liquid water oceans, billions of years ago, before the greenhouse spiral boiled them away. If so, the hottest planet in the solar system might once have looked a little like home.
So the next time someone asks which planet is hottest, remember: in space, distance from the fire matters less than what you’re wearing.