An Epic, Planet-Scale Wave Has Been Hiding in The Toxic Clouds of Venus For Decades
Deep in the thick, poisonous clouds wrapped around Venus, the atmosphere is behaving very oddly. A giant, previously unknown planet-scale wall of cloud travels westward around the planet every 4.9 days - and apparently has been doing so since at least 1983.
It can extend up to 7,500 kilometres (4,660 miles) long, stretching across the equator to both the north and south mid latitudes, at relatively low altitudes between 47.5 and 56.5 kilometres. It's a phenomenon that's never been seen anywhere else in the Solar System.
"If this happened on Earth, this would be a frontal surface at the scale of the planet," said astrophysicist Pedro Machado of the Institute of Astrophysics and Space Sciences in Portugal.
"That's incredible." ...
The new feature is different. It's much deeper than any atmospheric wave ever seen before on Venus, occurring in the cloud layer responsible for the greenhouse effect that makes the surface so scorchingly hot.
Careful analysis, as well as a study of past observations, showed that the feature has been recurrent, but heretofore unnoticed, since at least 1983, since it could only emerge through a collection of observations from a large number of instruments over a period of time. ...
The newly identified feature, the researchers found, can span up to 7,500 kilometres, and circles the planet once every 4.9 days at a velocity of around 328 kilometres per hour (204 miles per hour). That's a little faster than the clouds at this level, which have a rotation period of about 5.7 days.
But it's still unknown what causes it. ...