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Seen from Earth, Venus is a featureless ball; even the most powerful Earth-based telescope shows only clouds and more clouds. But those clouds are moving fast. The winds on Venus are powerful, circulating around the planet in just a matter of days. But because of Venus’ high temperatures and intense atmospheric pressure, they don’t behave like the winds on other planets.
The atmosphere of Venus extends up from the surface of the planet, up to an altitude of about 250 km. Down at the surface, the air pressure is 93 times higher than what we experience here on Earth. But once you rise up in altitude, the pressure drops to Earth surface pressure and then even lower.
At the very top of the cloud layers on Venus, wind speeds reach 355 km/hour (or 100 meters/second). This is the same the jet stream here on Earth. As you descend through the cloud layers, though, the wind speeds pick up. In the middle layer, the winds can reach speeds of more than 700 km/hour. That’s faster than the fastest tornado speed ever recorded on Earth.
But then as you descend further down through the clouds, the thickening atmosphere slows the winds down, so that they act more like currents in the ocean than winds in the atmosphere. Down at the surface, the winds only move at a few km/hour. That’s not much, but the thick atmosphere can still kick up dust and push around small rocks.
The winds on Venus travel in a westerly direction, the same backwards direction that Venus rotates. Seen from above, Venus rotates in a clockwise direction. This is backwards from the other 7 planets, which rotate counter-clockwise.
We have written many articles about Venus for Universe Today. Here’s an article about Venus’ wet, volcanic past, and here’s an article about how Venus might have had continents and oceans in the ancient past.
Want more information on Venus? Here’s a link to Hubblesite’s News Releases about Venus, and here’s a link to NASA’s Solar System Exploration Guide on Venus.
We have recorded a whole episode of Astronomy Cast that’s only about planet Venus. Listen to it here, Episode 50: Venus.