New Mars images reveal hidden traces of a recent ice age

New images from Mars, captured by the High Resolution Stereo Camera on ESA's Mars Express, reveal signs of a recent ice age on the Red Planet. The images focus on the Coloe Fossae region, located at 39°N latitude, where long, shallow grooves and valley structures suggest the presence of ancient glaciers.

These features, known as lineated valley fill and concentric crater fill, were formed by slow-moving mixtures of ice and debris that once flowed across the surface. Similar to Earth's glaciers, these icy deposits eventually became buried under layers of rock, leaving behind distinctive textures visible today. The region also contains craters of varying ages, some eroded, some partially buried, indicating a long history of geological and climatic activity.

Mars's climate has undergone cycles of warming and cooling over millions of years, driven by changes in the planet's axial tilt. During colder periods, ice expanded from the poles into the mid-latitudes, and when temperatures rose, the ice retreated, leaving behind traces of its former presence. The Coloe Fossae area may have been covered in ice as recently as 500,000 years ago, marking the end of the planet's most recent ice age.

The images also show a sharp boundary between Mars's northern and southern terrains, known as Protonilus Mensae. This transition zone, visible in topographic maps, highlights the dramatic changes in elevation and erosion across the planet. Scientists believe these features provide key insights into Mars's climatic history and its potential for past habitability.

The Mars Express HRSC, developed by the German Aerospace Center, continues to provide valuable data on the Martian surface. The images were processed by the DLR Institute of Planetary Research and the Freie Universität Berlin, offering new perspectives on the planet's ancient climate and geological evolution.