The Martian twister rises up on a huge column of dust more than half a mile (800 meters)
high in the new image from the High Resolution Imaging Science Experiment (HiRISE) camera on NASA’s Mars Reconnaissance Orbiter. HiRISE captured the image on February 16, 2012, while the orbiter passed over the Amazonis Planitia region of northern Mars. In the area observed, paths of many previous whirlwinds, or dust devils, are visible as streaks on the dusty surface. The 100 foot wide (30-m) dust devil curves slightly, pushed by a westerly breeze. Tracks from previous whirlwinds are also visible in the Mars twister picture, showing up as streaks on the Red Planet’s surface. The dust devil’s shadow can also clearly be seen in the photo. Dust devils occur on both Earth and Mars. They are spinning columns of air, made visible by the dirt they suck up off the ground. Unlike a tornado, a dust devil typically forms on a clear day when the ground is heated by the sun, warming the air just above the ground. As heated air near the surface rises quickly through a small pocket of cooler air above it, the air may begin to rotate, if conditions are just right. The Mars Reconnaissance Orbiter has been examining Mars with six science instruments since 2006. Now in an extended mission, the orbiter continues to provide insights into the planet’s ancient environments and how processes such as wind, meteorite impacts and seasonal frosts continue to affect the Martian surface today. This mission has returned more data about Mars than all other orbital and surface missions combined.