Bright and Dark Slope Streaks

Slope streaks are common in the tropics of Mars. Once thought to be caused by flowing water, most scientists now believe that they are avalanches of dust. They are typically darker than their surroundings and often fan outwards downslope. This suggests that the dust sediment is sticky, so that the avalanche broadens as it flows downhill. Slope streaks are known to fade over time, but the slope streaks at this monitoring site in Arabia Terra go beyond that.