The streaks, instead of being caused by small explosions, are instead the result of wind. These, too, must indicate periods when the wind was strong enough to move materials, consistently, in only one direction. The sand that makes up the north polar dunes is dark. Each spot and streak is composed of the dune sand. The bright surfaces are all covered with frost.
Illumination is from the lower left.
The 200 meter scale also indicates a distance of 656 feet. Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission.