Bright and dark streaks on Mars

This image captures prominent bright and dark streaks on slopes in the ancient Locras Vallis region on Mars.

The image was taken in the early martian morning on 20 June 2019 by the CaSSIS camera onboard the ESA/Roscosmos ExoMars Trace Gas Orbiter.

The brighter streaks are facing northeast; their photometric characteristics may depend on lighting geometry. The exact relationship between bright and dark slope streaks is still debated but the leading theory suggests that are formed by a dry avalanching process.

The image is centred at 10.6ºN/41.6ºE. North is up.