NASA's Opportunity rover captured a remarkable image of a dust devil twirling across Mars' surface on April 1. Experts say this is one of the best dust devils ever recorded in the Red Planet's Meridiani Planum region.
Captured from the rim of Mars' 14-mile-wide Endeavour Crater, the image shows the rover's tracks in the foreground and a Martian twister swirling off in the distance. While these extraterrestrial whirlwinds occur fairly regularly on Mars, catching one in action is a special treat.
Much like desert storms on Earth, dust devils on Mars form from spinning columns of air that carry dust and dirt high up into the atmosphere. They are largely driven by solar heating and are therefore most commonly seen on clear, sunny days. However, despite their appearance, dust devils do not cause the kind of damage true tornadoes do on Earth.
NASA's Opportunity rover landed on Mars in January 2004, only a few short weeks after its twin, Spirit. Both robots are part of a surface mission aimed to find signs that liquid water once flowed across the red planet. Originally, this mission was planned to last just three months, but Spirit and Opportunity kept exploring - even though it has since uncovered plenty of such evidence.
Previously, a Martian dust devil extending more than half a mile high was caught on camera by NASA's Mars Reconnaissance Orbiter, as it passed over the Red Planet's Amazonis Planitia region in 2012. And while dust devils have eluded Opportunity for much of its 12-year stay on Mars, Spirit photographed one in an area known as the Gusev Crater in 2005.
Unfortunately, Spirit was declared dead in 2011 after losing communication with Earth and getting stuck in a sand trap. But Opportunity is still going strong. In fact, the tireless rover broke the record for the greatest distance traveled on the surface of a world other than Earth in the summer of 2014. Currently, Opportunity's odometer reads 26.53 miles.
What's interesting about the area in which Opportunity spotted the recent dust devil is that there are believed to be underlying clays. This, scientists say, could unveil more about Mars' mysterious wet past, as clays minerals are typically created through chemical processes with ancient surface water.
