Scientists Uncover Ocean-Sized Reservoir of Liquid Water on Mars – Could It Support Alien Life?

A new study has revealed a gigantic volume of liquid water lying under the surface of Mars, sufficient to cover the entire planet in an ocean a mile deep. It is a ground-breaking finding from a team at the University of California, Berkeley, and UC San Diego, published in Proceedings of the National Academy of Sciences. The findings further the debate on several questions regarding life, as it were, about the Red Planet that contains the necessary conditions to support extraterrestrial organisms.

The researchers used seismic data recorded by NASA's InSight lander from quakes, volcanic activity, and meteor impacts to a hidden water reservoir on Mars. By using rock physics models similar to those on Earth, which locate underground aquifers and oil fields, they could locate water trapped in tiny fractures and pores some 11.5-20 kilometers below the Martian surface. The newly detected reservoir is beyond access with today's technology, but it can still provide important insights into the history of Mars and its habitability.

Michael Manga, a Berkeley professor of earth and planetary science and one of the study's authors, thinks these kinds of deep subsurface environments on Mars could support life. "We haven't found any evidence for life on Mars, but at least we have identified a place that should, in principle, be able to sustain life," says Manga. This view would mean that Mars could still have sites fit for supporting microbial life despite being, in general, an arid planet.

Although Mars is regarded as a desert planet today, large volumes of water used to be on the planet a long time ago. Ancient river valleys and lake bottoms are major geological features that testify to the liquid water that once existed on the surface during very ancient times on Mars. This finding of this underground reservoir implies that a substantial fraction of this water may have actually been lost to the crust of the planet rather than disappearing totally into space. This changes our view of Mars' watery past and its evolution, showing a more complicated history than previously thought.

The research also acknowledges several uncertainties. Investigating a planet's historical water reserves involves a great many assumptions, not least that Martian rock physics was similar to Earth rock physics. As such, while the current data suggests a water-saturated mid-crust, the volume and exact depth of the reservoir are still purely speculative. That, again, reflects more universal problems with planetary science and the challenge of mapping such hidden resources with any degree of accuracy.

According to Vashan Wright, a coauthor of the research paper and a professor at UC San Diego's Scripps Institution of Oceanography, these results are important. "Understanding the Martian water cycle is central to understanding the evolution of the planet, its surface, and its climate," said Wright. Knowing where that water resides, how much exists serves as the first stepping stones into deciphering the intricate geological and climatic history of Mars.

Putting this depth of underground water into perspective, the Kola Superdeep Borehole in Russia is the deepest hole dug by humans on Earth, reaching a depth of 12,262 meters. By way of comparison, this depth is shallow compared to end estimates for the water reservoir on Mars, putting a premium on the problems that deep drilling presents. In this light, an ambitious objective to dig deeper than this remains in the future for exploration, showing current technology's shortcomings.

It opens new avenues for understanding the Martians' potential to host life. At the current technic level, any future attempt to access this water would be futile. In overview, the research adds key insights into the history of water on Mars and its habitability. Such findings could help scientists as they continue to explore Mars in future missions and again deepen our knowledge of the enigmatic past of the Red Planet.