14 DAY TRIAL // An international collaboration of experts, featuring scientists from the American space agency, recently managed to shed new light on the intricate phenomena taking place in the atmosphere high above the surface of Venus. Researchers were apparently wrong to think of the planet as being really boring.
Thus far, planetary scientists believed that they could not possibly discover anything interesting in the Venusian atmosphere. Earlier scans have shown that the work is extremely hot, with average atmospheric temperature levels reaching about 800 degrees Fahrenheit (426ºCelsius).
A massive blanket of sulfuric acid clouds obscured the planetary surface, where pressure levels are 90 times higher than those on Earth. As such, no manned missions are planned to explore the surface of the planet. But experts failed to focus their attention on the upper atmosphere.
This is precisely what the new study did. Astronomers used infrared telescopes to peer in a section of the atmosphere about 110 kilometers (68 miles) above the surface. This area encompasses both the Venusian mesosphere and the thermosphere.
“Any variability in the weather on Venus is noteworthy, because the planet has so many features to keep atmospheric conditions the same,” National Center for Earth and Space Science Education researcher Dr. Tim Livengood explains. He is now based at the University of Maryland.
“Although the air over the polar regions in these upper atmospheric layers on Venus was colder than the air over the equator in most measurements, occasionally it appeared to be warmer,” NASA Goddard Space Flight Center expert Dr. Theodor Kostiuk adds.
He explains the upper Venusian atmosphere revealed an effect opposite to the Hadley cell circulation pattern experts see on Earth. On our planet, the pattern takes warm air from the Equator, raises it at high altitudes, and then takes it to the poles, where it cools down and drops to the surface.
“We saw the opposite on Venus. In addition, although the surface temperature is fairly even, we've seen substantial changes – up to 54 degrees Fahrenheit (about 30ºK change) – within a few Earth days in the mesosphere – thermosphere layers over low latitudes on Venus,” Kostiuk explains.
Temperatures at the poles appeared to hold within more stable boundaries. Still, the team noticed variations of as much as 15ºK (27ºFahrenheit) within the same time interval. Details of the study appear in a recent online issue of the esteemed journal Icarus.
“The mesosphere and thermosphere of Venus are dynamically activw. Wind patterns resulting from solar heating and east to west zonal winds compete, possibly resulting in altered local temperatures and their variability over time,” University of Cologne expert and lead study author Dr. Guido Sonnabend concludes.