You expected to find seas, mountains—maybe even a few trees—on a planet considered “Earth’s twin.” Instead, Venus is like Earth in reverse. A day here lasts longer than a year, the sun rises in the west and sets in the east, and—whew!—is it ever hot outside! Venus’ average temperature is more than six times hotter than the hottest spot on Earth. That’s hot enough to turn a slab of lead into a molten puddle. Sunset won’t bring relief from the scorching heat. Day or night, from its north pole to its south pole, every day of the year, Venus is locked in a perpetual heat wave. Blame the blanketing atmosphere, more than 90 times thicker than Earth’s, of carbon dioxide. Good thing your spacesuit has air conditioning!
How did such a harsh planet earn the title of Earth’s twin? Venus is roughly the same size and density as Earth, which means the gravity is similar between here and home. The view from the scalding surface isn’t all that alien, either. Like Earth, Venus has clouds and wind—although the clouds are made of sulfuric acid and the wind exceeds tornado strength. The sunlight filtering from above bathes the landscape in a dim red glow. You’ll never spot Earth through those heavy clouds, but rest assured that your friends back home can see you. Venus is the brightest object in Earth’s sky after the moon.