Venus may appear as a brilliant, peaceful point of light in Earth’s sky, but beneath its reflective clouds lies a world of crushing pressure, extreme heat and unusual geology. From an atmosphere that races around the planet to enormous lava channels and volcanoes that may still be active, our nearest planetary neighbor is filled with surprises. Here are ten of the most remarkable facts about Venus.
1. Venus Is Hotter Than Mercury
Although Mercury is closer to the Sun, Venus is the hottest planet in the solar system. Its average surface temperature is about 867°F (464°C), while temperatures on Mercury rise to around 800°F (430°C) during the day before falling dramatically at night.
Venus remains intensely hot because its dense carbon dioxide atmosphere traps heat through an extreme greenhouse effect. Its thick atmosphere also distributes that heat around the planet, so temperatures vary remarkably little between day and night or between the equator and poles.
2. One Rotation Takes Longer Than a Venusian Year
Venus takes about 243 Earth days to complete one rotation on its axis but only 224.7 Earth days to orbit the Sun. In that sense, a day on Venus lasts longer than its year. The interval from one sunrise to the next is shorter—about 117 Earth days—because the planet is also moving around the Sun as it rotates.
Venus also spins in the opposite direction from most planets. An observer on its surface, if the clouds permitted a view of the Sun, would see it rise in the west and set in the east.
3. Its Atmosphere Circles the Planet in About Four Days
Venus rotates extremely slowly, but its upper atmosphere races around the planet in only about four Earth days. Winds near the cloud tops can exceed 220 mph (360 km/h), moving dozens of times faster than the solid planet beneath them.
This phenomenon is known as atmospheric super-rotation. The winds generally travel in the same westward direction as Venus rotates, carrying its thick cloud cover around the planet roughly 60 times during the time Venus itself completes a single rotation.
4. Surface Pressure Is Like Being 3,000 Feet Underwater
Atmospheric pressure at the surface of Venus is about 92 times greater than at sea level on Earth. That is comparable to the pressure experienced nearly 3,000 feet (900 meters) beneath Earth’s oceans.
This crushing pressure results from the immense weight of Venus’s carbon dioxide atmosphere. Any spacecraft reaching the surface must therefore withstand both the pressure and extreme heat—one reason the longest-surviving Venus landers operated for only a little over two hours.
5. Venus May Still Have Active Volcanoes
Venus contains vast volcanic plains, immense shield volcanoes and hundreds of thousands of smaller volcanic features. Comparisons of radar images taken by NASA’s Magellan spacecraft revealed that a vent near Maat Mons changed shape and grew larger between two observations made in 1991—strong evidence that an eruption occurred during the mission.
Venus also has unusual volcanic structures known as pancake domes. These broad, flat-topped formations were created by thick, highly viscous lava that spread slowly before solidifying. Some extend more than 40 miles (65 kilometers) across while rising less than a mile above the surrounding terrain.
6. Sulfuric-Acid Rain Never Reaches the Ground
Venus’s thick clouds are composed largely of sulfuric-acid droplets rather than water. Some of these droplets fall from the cloud layer as precipitation, creating a form of acid rain high in the atmosphere. However, the increasingly intense heat below the clouds prevents it from reaching the surface.
As the droplets descend, they evaporate and break apart roughly 16 miles (25 kilometers) above the ground. Venus therefore has rain that vanishes long before it can touch the planet’s scorched landscape.
7. Venus Has Huge Ring-Shaped Structures Called Coronae
Hundreds of enormous circular and oval structures called coronae are scattered across Venus. They are surrounded by rings of fractures, ridges and trenches and can extend for hundreds of miles across. The largest, Artemis Corona, is roughly 1,300 miles (2,100 kilometers) wide.
Coronae probably form when hot material rises through Venus’s mantle and pushes the crust upward. As the uplifted region later cools or sinks, the surface fractures and collapses around its edges, leaving a vast ring-shaped pattern unlike any common landform on Earth.
8. Baltis Vallis Is the Solar System’s Longest Known Channel
Baltis Vallis winds across Venus for about 4,200 miles (6,800 kilometers), making it the longest known channel in the solar system. Although it resembles an immense river, it was carved by extremely fluid lava rather than water.
The channel twists across volcanic plains and is difficult to trace in places because later lava flows and geological activity have buried sections of it. Its full length may therefore be even greater than the portion revealed by radar mapping from NASA’s Magellan spacecraft.
9. Its Atmosphere Filters Out Most Small Impact Craters
Venus has roughly 1,000 known impact craters, but very few are smaller than about 1.2 miles (2 kilometers) across. Its dense atmosphere causes most small incoming objects to burn up, break apart or slow dramatically before reaching the surface.
Larger objects can survive the descent, sometimes fragmenting and creating groups of nearby craters. The craters that do form are distributed relatively evenly across Venus, indicating that much of the visible surface is geologically young and has been extensively altered by volcanic and tectonic activity.
10. Venus Is Bright Enough to Make Objects Cast Shadows on Earth
Venus is the brightest planet in Earth’s sky and can reach an apparent magnitude of about –4.9. Its thick clouds reflect most of the sunlight that strikes them, while its proximity to Earth makes it appear far brighter than any star.
Near its greatest brilliance, Venus can provide enough light for trees, posts and even people to cast faint shadows. The effect requires an exceptionally dark, moonless location away from artificial lighting, but it means that a planet millions of miles away can visibly illuminate the ground beneath your feet.