What To Know
- On August 15, 2022, a small pit on Mars, located in the flank of the extinct volcano Arsia Mons, captured the attention of scientists.
- They could be lava tubes similar to those seen on the Moon and Earth, formed when the volcano was active, now revealed by erosion and collapse of the tube roof.
- The presence of these pits on the flanks of volcanoes also suggests a close link with Past volcanic activity on the red planet.
On August 15, 2022, a small pit on Mars, located in the flank of the extinct volcano Arsia Mons, captured the attention of scientists. Photographed by NASA‘s Mars Reconnaissance Orbiter, this opening, just a few meters in diameter, could reveal secrets buried beneath the Martian surface.
A refuge for life on Mars?
On Mars, the region of Tharsisdotted with giant volcanoes including Arsia Mons, has intriguing pits. Scientists wonder whether these structures are simple vertical shafts or whether they lead to larger caverns. They could be lava tubes similar to those seen on the Moon and Earth, formed when the volcano was active, now revealed by erosion and collapse of the tube roof. These pits and caves are of particular interest for several reasons. In particular, they could offer a natural refuge for future astronauts. With its thin atmosphere and lack of a global magnetic field, Mars does indeed expose its surfaces to harmful space radiation. If they lead to caverns, these pits could therefore house astronauts’ equipment and habitats, protecting them from radiation. In addition to their useful potential for humans, these pits could also have a astrobiological importanceThey could have served as sheltered refuges for past and perhaps even present-day Martian microbial life.
Volcanic or tectonic activity?
The presence of these pits on the flanks of volcanoes also suggests a close link with Past volcanic activity on the red planet. As a reminder, lava tubes form when molten lava flows beneath the surface. Once the volcano dies, these tubes empty, leaving underground cavities. If the roof of these tubes partially collapses, the result is pits like those seen on Arsia Mons. Martian pits can also form through tectonic processes where the surface fractures under geological stress. These tectonic pits would be less likely to lead to caverns. Another possibility, less likely but fascinating, is that these pits are remnants of underground rivers that existed billions of years ago. On Earth, similar formations called karsts form when limestone dissolves, creating pits and caverns.
Another crater on Arsia Mons again imaged by the HiRISE instrument on the Mars Reconnaissance Orbiter. Credits: NASA/JPL-Caltech/UArizona
In search of answers
For now, these hypotheses remain speculative. Only future missions will be able to provide concrete answers by exploring these pits in depth. These structures could thus become privileged targets for future robotic or human missions. Airborne missions, inspired by the success of NASA’s Ingenuity helicoptercould notably fly over and explore these pits in more detail. In summary, the discovery of this pit on Arsia Mons opens new perspectives for Martian exploration. It could reveal valuable information about Mars’ volcanic past and offer practical solutions for future human missions. By exploring these underground mysteries, we could not only better understand the geological history of Mars, but also prepare the future of human exploration on the Red Planet.
