October 8, 2012
Venus Clouds Are Evidence Of Vigorous Circulation
Lee Rannals for redOrbit.com - Your Universe Online
An image released by the European Space Agency shows how not-alike Earth's twin planet really is.
The spacecraft took the image 18,600 miles above the surface of Venus, showing the planet's 12 mile-thick carbon dioxide and sulphuric dioxide haze.
The ultraviolet light image taken by Venus Express shows the planet's southern hemisphere, with the south pole at the bottom of the frame and the equator close to the top.
The visible top cloud layer seen in the image is about 43 miles above the planet's surface.
In the image, bright and dark patterns can be seen that are caused by variations in an unknown absorbing chemical at the Venus cloud tops. The planet's low latitudes make this region look dark in ultraviolet light.
In the higher latitudes, the ultraviolet light is masked by a thick haze of reflecting aerosol, making it appear brighter.
ESA said the shapes of the cloud top features are evidence of vigorous circulation and dynamics in the planet's atmosphere.
At lower latitudes, you can see mottled cloud formations associated with turbulent activities, while smooth laminar flows are visible at the middle of the higher latitudes.
Scientists are able to calculate the wind speed on the planet from tracking cloud features as they wrap around the planet. ESA said that this takes place at faster than 328 feet per second.
Venus' atmosphere completes one circuit every four Earth day, while the planet's surface takes 224 days to complete one revolution on its axis.