Mars is covered with weird-looking geological formations and this is no exception. As spied by the High Resolution Imaging Science Experiment (HiRISE) camera aboard NASA’s Mars Reconnaissance Orbiter (MRO) orbiting 170 miles above, this messed-up heart shape is located on the Red Planet’s famous Tharsis Bulge, a region home to some of Mars’ biggest ancient volcanoes.
The heart, which was most likely formed through volcanic activity itself, was spotted south of the huge shield volcano Ascraeus Mons and measures approximately 200 meters across (a little under twice the length of a football field). The feature is multi-layered and rises above the surrounding landscape.
“Perhaps this feature is an ancient vent structure (an opening in the ground from which volcanic lava emerges) that has been more resistant to erosion than the surrounding area, so that it resembles ‘inverted’ terrains,” writes planetary scientist Ramy El-Maarry.
Inverted terrains often occur when some part of the landscape becomes hardened to erosion. In this case, the candidate vent is composed from ancient lava that likely pooled inside a depression or valley. After the lava cooled and the surrounding landscape became eroded, the raised multi-layer feature emerged creating the ringed heart shape that can be seen today. This is a process known as “topographic inversion.”