Dust and sand slide down slopes on Mars in little avalanches.
Dark slope streaks are thought to be the result of the relatively bright colored dust avalanching down slopes, revealing the darker, coarser sand underneath.
This image is the latest in a sequence of images of this crater that started in 2013. The goal is to watch the dusty slopes, and try to understand more about the processes that drive these little avalanches.
An animation shows this sequence of 14 images taken over seven Earth years (about 3 and a half Mars years), and shows where new streaks have occurred on the slopes of this crater. The shape of the crater’s rim appears to “wobble” because the spacecraft looks at the crater from slightly different directions. This could be corrected by creating a 3D terrain model and properly projecting each image onto it.