Though the weather on Venus was thought to be 800 degrees Fahrenheit, with sulfuric acid clouds, NASA scientists were astonished when they noticed strange temperature variations occuring higher up in the planet's atmosphere during a routine study.
Dr. Theodor Kostiuk and Dr. Tim Livengood were studying old data from telescopic observations from NASA and international scientists when they found unusual variations within the atmospheric temperature never before seen.
The distinctions in temperature, seemingly contradictory compared with the stagnant climate on Venus, were observed in infrared light nearly 70 miles above the surface of Venus in layers above the acidic clouds called the mesosphere and the thermosphere.
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, Dr. Kostiuk said in a NASA press release.
Venus is typically known for an unpleasant, unchanging climate at 800 degrees Fahrenheit, covered in think clouds of sulfuric acid and an atmospheric pressure 90 times higher than Earth's. However, the varying activity found in the mesosphere and thermosphere of Venus proved be an observation that surprised scientists.
Any variability in the weather on Venus is noteworthy, because the planet has so many features to keep atmospheric conditions the same, Dr. Livengood told NASA.
While Earth has a circulation pattern called the Hadley cell, which pushes warm air to the equator where it cools and sinks before being compressed to warm the upper atmosphere over Earth's poles, Venus did the exact opposite, according to Dr. Kostiuk.
Data, ranging from days to an entire decade, showed substantial changes of up to 54 degrees Fahrenheit in the mesosphere and thermosphere layers and 27 degrees Fahrenheit in the poles according to Dr. Kostiuk.
We saw warmer temperatures than those predicted for this altitude by the leading accepted model, the Venus International Reference Atmosphere model, said Dr. Kostiuk. This tells us that we have lots of work to do updating our upper atmospheric circulation model for Venus.
The researchers compared observations from 1990 to 1991 from Goddard at NASA's Infrared Telescope Facility to observations from the Cologne Tunable Heterodyne Spectrometer from 2009. They measured the temperature using infrared light emitted from a spectrometer.
The variety of temperatures in the upper atmosphere over the past decade could be caused by turbulence from global air currents at different altitudes or even giant vortexes that swirl around the poles of Venus, according to the team. Also, the temperature change could stem from sunlight intensity changing from day to evening or from flares or coronal mass ejections.
The team hopes that this new information regarding the variety of temperatures on Venus' atmosphere can give insight to the reasons why life does not exists on Venus.