HiRISE Picture of the Day: 19 February 2026 
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Lavas over Clay-Rich Terrain

Lavas over Clay-Rich Terrain
To human eyes, the surface of Mars appears as various shades of red, but HiRISE is also sensitive to near-infrared light. This allows HiRISE to distinguish subtle differences in surface composition, especially in complex terrains.

Here we see materials at the northern edge of Syrtis Major, one of the largest volcanoes on Mars. Lavas from this volcano are typically rich in iron and magnesium-bearing minerals, which give them a dark bluish tone in HiRISE enhanced color images. These lavas flowed on top of older clay-rich sedimentary rocks near the Nili Fossae region west of Jezero Crater.

In a closeup, the older clay-rich layers display striking orange and pink tones. These ancient rocks are crosscut by fractures, and smaller ripples of bluish sand are visible across the surface.

ID: ESP_090751_1985
date: 5 December 2025
altitude: 277 km

https://uahirise.org/hipod/ESP_090751_1985
NASA/JPL-Caltech/University of Arizona
#Mars #science #NASA

Black & white is less than 5 km across; enhanced color is less than 1 km. For full observation details, visit the ID link.