ASA believes such a global dust storm was responsible for ending the Mars Opportunity rover’s mission in 2018. Two technical papers recently described a phenomenon observed within the storm: dust towers. These are concentrated clouds of dust that warm in sunlight and quickly rise high into the air. NASA believes dust-trapped water vapor may have ridden these clouds into space, where brutal solar radiation tears their molecules apart. This may help explain how Martian water disappeared over aeons.
Dust towers are massive, churning clouds far denser and climb much higher than normal background dust in the thin Martian atmosphere. While they also occur under normal conditions, the freak weather phenomena appear to form in greater numbers during global storms. A dust tower starts at the planet’s surface as an area of rapidly lifted dust the size of Hampshire. By the time a tower reaches a height of 50 miles (80km), as seen during the 2018 global dust storm, it may be as wide as Wales.
As the tower decays, it can form a layer of dust 35 miles (56km) above the surface potentially wider than the continental United States. The recent findings on dust towers come courtesy of NASA’s Mars Reconnaissance Orbiter. Though global dust storms cloak the planet’s surface, NASA’s unmanned Mars orbiter uses its heat-sensing Mars Climate Sounder instrument to peer into the haze. The cutting-edge instrument is specifically designed for measuring dust levels.
The data, coupled with images from a camera aboard the orbiter called the Mars Context Imager (MARCI), enabled scientists to detect the monstrous dust towers.
Dr David Kass, a NASA Mars Climate Sounder scientist, said, Global dust storms are really unusual. We really don’t have anything like this on the Earth, where the entire planet’s weather changes for several months.
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