Discovery of vast water reservoir on Mars suggests potential habitability

Scientists, using seismic studies of Mars' interior, have discovered evidence of a vast underground reservoir of liquid water. This discovery suggests that there is a place on the Red Planet that could potentially support life. Unfortunately, it is not easily accessible.

Data gathered by NASA's InSight lander suggest that beneath the surface of Mars, there is such a large amount of water that it could cover the entire planet with an ocean between 1 to 2 kilometres deep. Although this is good news for those interested in the fate of water on the planet after its oceans disappeared over 3 billion years ago, the discovered reservoir won't be very useful for future Martian colonies.

The water is hidden in microscopic cracks and pores in rock in the middle crust of Mars at a depth of 11 and 20 kilometres below the surface. Even on Earth, drilling a hole a kilometre deep is a major challenge. On the Red Planet, such tasks are even more difficult. However, the discovery points to another promising site for searching for life on Mars if access to this reservoir can be obtained. For now, its existence helps answer questions about the planet's geological history.

Vashan Wright from the University of California, San Diego, author of the study described in "Proceedings of the National Academy of Sciences," explains that "knowing the Martian water cycle is key to understanding the evolution of the planet's climate, surface, and interior." He adds that "a useful starting point is determining where the water is and how much of it there is."

Scientists used a mathematical model of rock physics, identical to models used on Earth, to map underground water reservoirs and oil deposits. This allowed them to infer that the seismic data from InSight is best explained by assuming the existence of a deep layer of fractured magmatic rock saturated with liquid water. Magmatic rocks are cooled hot magma, similar to the granite of the Sierra Nevada.

Prof. Michael Manga, one of the scientists, says that "the finding that there is a large reservoir of liquid water gives some insight into what the ancient climate of Mars was like or could have been." He adds that "water is necessary for life as we know it. I see no reason why an underground reservoir wouldn't be a habitable environment. It certainly is on Earth—deep mines are habitats for life, the ocean floor is a habitat for life. We haven't found any evidence of life on Mars, but at least we've identified a place that fundamentally should be able to support life."

According to scientists, various formations—river channels, deltas, lake deposits, and water-altered rocks—support the hypothesis that water once flowed on the planet's surface. However, this wet period ended over 3 billion years ago after Mars lost its atmosphere. Many probes and landers have been sent to the planet to check what happened to the water. The polar ice cannot explain everything. It is also unknown whether life exists or exists on the planet. New discoveries suggest that most water didn't escape into space but seeped into the crust.

NASA's InSight lander reached the surface of Mars on November 26, 2018. It is an acronym for Interior Exploration, which uses Seismic Investigations, Geodesy, and Heat Transport. Its main task was to study the interior of the Red Planet, including monitoring seismic activity. During its mission, it detected over 1,300 "Marsquakes," providing scientists with valuable data on the planet's structure. Over 1,200 mission days, InSight encountered extreme environmental conditions that caused a massive dust buildup on its solar panels. This buildup of dust, which prevented the generation of sufficient power, forced the lander to end its mission.

One of InSight's most important discoveries was detecting the largest recorded earthquake on Mars. On May 4, 2022, at 7:00 AM ET, an earthquake with a magnitude of 4.7 on the Richter scale was recorded. This event provided valuable information on the planet's seismic activity, indicating that Mars also experiences tectonic movements despite the lack of plate tectonics known from Earth. The InSight mission significantly brought scientists closer to a better understanding of geological processes on Mars. The data it collected will be fundamental for future manned missions to the Red Planet, helping in planning landings and operations on its surface.