Twister! A towering, twisting dust devil dancing across the face of Mars is among Mother Nature's latest work on Earth's planetary neighbor. The dust plume stretches more than a half-mile high and casts a serpentine shadow in the Amazonis Planitia region in northern Mars. The image was captured Feb. 16 by NASA's Mars Reconnaissance Orbiter. The dust devil is about 30 meters (100 feet) in diameter. The arc partway up the plume was caused by a westerly breeze. Winds on Mars -- like Earth -- are caused by solar heating.
Mystery Cloud The verdict is still out as to what caused this cloud or projection rising from the edge of the Martian disk. Amateur astrophotographer Wayne Jaeschke took this picture on March 22.
Winter Frost Frost, fog and clouds cover the rim of Mars' Lomonosov Crater, a lava-filled basin located in the planet's northern plains.
Avalanche! NASA's Mars Reconnaissance Orbiter catches the first image of an avalanche on another planet. The picture, which was digitally rescaled, shows layers of white ice thawing over red rock. The darker colors toward the right are where there was less ice in the soil. As the cliff thawed, ice fell more than 700 meters (2,300 feet) to the ground, causing plumes of ice and dust to rise and cast shadows in the springtime sun.
Dust Devil Another view of a dust devil on Mars, this one snapped by the Mars Global Surveyor, shows the swirling cloud climbing a crater wall and its dark trail. Dust devils are spawned when air is heated by a warm surface and begins to spin as it rises. The pillars can stretch 5 miles into the sky, but they usually last just a few minutes.
Spring Thaw Ah, springtime on Mars. A time when the dry ice cracks and sand escapes from the dunes below. This image, taken by the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter, shows bluish cracks in the carbon dioxide ice covering dunes on the planet’s north pole. The dark fan-shaped deposits around the edges of the dunes are places where the carbon dioxide ice has sublimated, or transformed directly into gas, which causes ruptures in layer of dry ice. That allows underlying sand to escape, where it is picked up and blown by the wind.
Global View Bluish-white water ice clouds hang above Mars’ Tharsis volcanoes. The computer-generated image was created by wrapping images made by Mars Global Surveyor into a sphere.
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