Dust devils are a common feature on the Martian surface, but seeing one of these extraterrestrial whirlwinds in action through the eyes of a Mars rover is a special joy.
ANALYSIS: Dust Devil 'Swarm' Races Across Martian Plain
Seen here is a picture-perfect scene from the rim of Endeavour Crater, including rover tracks, fascinating Mars geology and an awesome atmospheric phenomenon.
NASA's Mars rover Opportunity was busy navigating its way up the north-facing slope of "Knudsen Ridge," which is bordering the southern edge of "Marathon Valley." This region is of interest to planetary scientists as orbital measurements suggest the presence of clays. These minerals were created through chemical processes with ancient surface water, so rover scientists are keen for Opportunity to study them in the hope of unraveling more mysteries of Mars' wet past.
But along the way, on March 31, Opportunity was looking back at its tracks rolling up Knudson Ridge to see the impressively-formed dust devil swirling in the valley below.
PHOTO: Dust Devils Rip Up Mars' 'Etch A Sketch' Surface
Opportunity hasn't seen many dust devils in its 12 years on the Martian surface. Its sister rover Spirit, however, was intimately familiar with these atmospheric phenomena at its area of study in Gusev Crater. But since Spirit became stuck in a sand trap and lost communication with Earth in 2010, we've mainly seen these whirling dervishes, and the dark tracks they create, through the lens of the High-Resolution Imaging Science Experiment (HiRISE) camera on board NASA's Mars Reconnaissance Orbiter (MRO).
Dust devils on Mars form in much the same way they do on Earth. A thin layer of air above the ground gets heated by sunlight and starts to rise. This air starts to rotate, creating a small pocket of low pressure, eventually creating a rapidly-spinning vortex. This vortex "sucks up" dust from the surface, revealing darker material underneath. It is believed that, in Mars' thin atmosphere, these dust devils carry out an important role in dust cycling, shaping the global climate of the Red Planet.
NEWS: Dust Devils' Powerful Updrafts Could Drive Mars Climate
Interestingly, these mini-tornados, that can span hundreds of meters in altitude, perform a very important role in the operations of solar powered surface missions. Occasionally they may spin over the solar panels of Opportunity, creating a "cleaning event," blowing away the accumulation of dust and giving the veteran robot explorer a critical power boost.