High-altitude hazes over Arabia Terra - Mars Express
High-altitude hazes over Arabia Terra imaged by the Mars Express HRSC instrument. These high altitude hazes are likely a form of noctilucent cloud. Their formation is poorly understood even on Earth. In this case, the clouds are likely related to the seasonal Aphelion Cloud Belt. This phenomenon occurs during the Martian spring and summer, when Mars is most distant from the Sun. The extra distance causes the atmosphere to cool substantially, allowing water ice clouds to form daily at equatorial latitudes for a few months.
This image was created using two limb-scan images taken through Mars Express' blue and green filters. These sequences are designed to study Martian atmospheric layers. These sequences require a complex geometric correction to resemble what a human eye might see. In addition, a red channel has been synthesized by subtracting blue channel data from the green channel data.
This image was taken during Mars Express' 15481st orbit of the red planet, March 19, 2016.
Image Credit: ESA/DLR/FU Berlin/J. Cowart, CC BY-SA 3.0 IGO