This HiRISE image captures a new, dated (within about a decade) impact crater that triggered a slope streak. When the meteoroid hit the surface and exploded to make the crater, it also destabilized the slope and initiated this avalanche.
The crater itself is only 5 meters across, but the streak it started is 1 kilometer long! Slope streaks are created when dry dust avalanches leave behind dark swaths on dusty Martian hills. The faded scar of an old avalanche is also visible to the side of the new dark streak. [More at link]