Dusty Water Ice in Mars' Terra Sirenum

This image from NASA's Mars Reconnaissance Orbiter (MRO) shows white material believed to be dusty water ice lining the edges of Martian gullies in a region named Terra Sirenum. Scientists believe dust particles within this ice act similarly to dust that falls onto glaciers on Earth, warming up in sunlight and causing subsurface pockets of meltwater to form. On Earth, the dust that builds up on glaciers is called cryoconite, and the pockets it forms are called cryoconite holes. These pockets of water on our planet are often teeming with simple life, including algae, fungi, and cyanobacteria. Scientists believe similar shallow pools of water could exist on Mars, and may also be excellent places to search for life on the Red Planet today. This enhanced-color image was captured by MRO's HiRISE (High-Resolution Imaging Science Experiment) camera on Dec. 25, 2016. The blue color at the bottom of the gullies is likely coarse sand (not ice); the hue would not actually be perceptible to the human eye. HiRISE is able to detect this color by looking at the scene in far-infrared wavelengths. https://photojournal.jpl.nasa.gov/catalog/PIA26407