A growing bounty of images from NASA’s Mars Reconnaissance Orbiter reveals that the timing of new activity in one type of the enigmatic gullies on Mars implicates carbon-dioxide frost, rather than water, as the agent causing fresh flows of sand.
A growing bounty of images from NASA’s Mars Reconnaissance Orbiter reveals that the timing of new activity in one type of the enigmatic gullies on Mars implicates carbon-dioxide frost, rather than water, as the agent causing fresh flows of sand.