Tempe Fossae: The 'red' that stands out in the Martian rainbow

By Maddie Stone

Everybody's been waving their rainbow flag recently, so it was only a matter of time before Mars got in on the fun. Admittedly, this image was painted in rainbow colors to highlight elevation changes. But I'd like to think that the progressive Martian societies of the future would agree with the color scheme.
The images shown here were captured by the high-resolution stereo camera on European Space Agency's Mars Express last November and released to the public today. We're looking at the Tempe Fossae, a heavily scarred landscape in the north-central portion of the Red Planet's western hemisphere. The Tempe Fossae comprises part of the Ascuris Planum, one of the most geologically diverse regions on the planet.

According to the European Space Agency:

Situated at the northeastern edge of the Tharsis volcanic province, this region is found close to the transitional zone between the ancient southern highlands and the young northern lowlands. It is characterised by a large variety of tectonic and volcanic structures with ages that span much of the Red Planet's geologic history.

As can also be seen in the colour image above, the region is criss-crossed by large numbers of linear and curvilinear features. These are most likely 'graben', products of the planet's crust having been stretched apart. Graben is the term given to the section of the crust at lower elevation, bordered by sets of parallel faults.

Scarred landscapes like this help scientists write the history of Mars, a planet that was probably much warmer, wetter, and more geologically active in the past. While most of the scar marks shown here run in parallel, a fainter set of troughs cross at an almost perpendicular angle, suggesting two distinct periods of tectonic stress and strain. The circular features that dot the terrain could indicate asteroid impacts, volcanic activity, or sinkholes from ancient groundwater.

If you're cool enough to keep a pair of stereoscopic glasses with red-green or red-blue filters on hand, another version of the image pops even more than the rainbow one.