Vortex on Venus Changes Shape Every Day

 

A giant vortex at the south pole of Venus is actually a shape-shifter that changes form at least once a day, at times bizarrely taking on the appearance of a giant letter "S" or the number "8," a new study reveals.

Venus, the second closest planet to the sun, possesses giant, hot and essentially permanent vortexes of clouds whirling fast at its poles. These result from how Venus' atmosphere circulates much faster than any other rocky planet's in the solar system — the cloud-level atmosphere of Venus on average spins 60 times faster than the planet's surface. 

This image shows the polar region of Venus, at a wavelength of 3.8 microns. The arrows denote the motion of the atmosphere around a center of rotation (marked with a white dot). The center of rotation is found to be displaced on average by about 300 km from the geographic south pole.

Past images suggested the roughly 1,200-mile-wide (2,000-kilometer) southern polar vortex was only a spinning oval shape. However, new infrared pictures from the Visible and Infrared Thermal Imaging Spectrometer (VIRTIS) on the European Space Agency's Venus Express mission revealed far more detail than past images, showing that the vortex's internal structure changes shape at least every 24 hours. Space.com