Dark Light
Gully and defrosting activity have been visible here along the edge of a dune field, along with blocks of frost.

Observations of the same area help us check for repeat activity, as well as measuring those meter-scale blocks that we’ve seen prior.

In this case, we want to compare any possible changes with a previous observation, which we acquired in 2011. We’ve also seen images where carbon dioxide frost was the driving process in creating new gullies, so we know their formation is occurring to this day. Tracking for changes, especially when we look at the 1-kilometer enhanced color swath, can help us find more.

This caption is based on the original science rationale.


Image: NASA/JPL/University of Arizona https://www.uahirise.org/hipod/ESP_039701_1095
Related Posts

River of Sand

A dominant driver of surface processes on Mars today is aeolian (wind) activity. In many cases, sediment from this activity is trapped in low-lying areas, such as craters.

Dunes in Meridiani Planum

HiRISE monitors dune fields across Mars to track how they are changing. The mobile sand also cleans dust off of the bedrock in inter-dune areas, providing good views of the bedrock structures and colors.