Massive Underground Water Reservoir Discovered on Mars—But There’s a Catch!

A recent study reveals the discovery of a massive reservoir of liquid water beneath the surface of Mars, with a volume so vast it could fill an ocean that would cover the entire planet. This water, trapped within fractures in igneous rocks, was identified through seismic data collected by NASA’s InSight Lander, which aimed to explore the interior of Mars. While this finding raises hopes for potential life on the red planet, it presents a significant challenge.

The water lies at depths ranging from 7.2 to 12.4 miles (11.5 to 20 kilometers) below the Martian surface, making it inaccessible with current technology. Although the conditions at these depths might be suitable for microbial life, reaching such depths is a daunting task, possibly beyond our current capabilities.

“At these depths, the crust is warm enough for water to exist as a liquid. At more shallow depths, the water would be frozen as ice,” explained Vashan Wright, a planetary scientist at the University of California, San Diego’s Scripps Institution of Oceanography, and the lead author of the study. The research was published in the journal *Proceedings of the National Academy of Sciences*.

Co-author Michael Manga of the University of California, Berkeley, noted that on Earth, microbial life has been found deep underground where rocks are saturated with water, drawing a parallel to what might be possible on Mars.

The discovery was made possible thanks to data from India’s Chandrayaan-2 lunar mission in 2019, which first indicated an abundance of water on the Moon. The InSight data then pointed to the presence of this vast water reservoir within igneous rocks in Mars’ crust. The InSight lander, which began its mission in 2018, studied Mars’ deep interior and collected data on its core, mantle, and crust before the mission ended in 2022.

Wright explained, “The water exists within fractures. If the InSight location is representative, and you extract all the water from the fractures in the mid-crust, we estimate that the water could fill a 1-2 km deep (0.6-1.2 miles) ocean on Mars globally.”

The discovery of this water is significant, particularly for future human missions to Mars, where water would be an essential resource. Although it was known that Mars holds water in the form of ice at its poles and beneath its surface, finding liquid water underground adds a new dimension to our understanding of the planet. However, the challenge of accessing this water remains formidable.

“Drilling to these depths is very challenging,” Manga noted. He suggested that searching for areas where geological activity might bring this water closer to the surface, such as the tectonically active Cerberus Fossae region in Mars’ northern hemisphere, could be an alternative approach to accessing deep liquids.