Huge hidden ocean beneath Mars could harbor life

Geophysicists have discovered a huge hidden ocean beneath the surface of Mars that they believe could harbor life. The giant underground reservoir, discovered using seismic data from NASA’s InSight lander, contains enough liquid to cover the entire planet with a mile of water. But that’s too deep to reach by known means. Reaching the water, which is trapped in layers of crushed rock 7 to 12 miles (11.5 to 20 kilometers) beneath the Martian crust, would require drilling that has yet to be done on Earth.

But if humans could one day reach it, the discoverers say it would be a promising place to look for life. The researchers published their findings in the journal Proceedings of the National Academy of Sciences (PNAS) on August 12. “Water is necessary for life as we know it,” study co-author Michael Manga, a professor of Earth and planetary sciences at the University of California, Berkeley, said in a statement. “I don’t see why [underground reservoirs] shouldn’t be habitable environments.

That’s certainly true on Earth, where deep, deep mines harbor life, and the ocean floor harbors life.” “While we haven’t found evidence of life on Mars, we have identified a place where, at least in principle, life could exist,” Manga added. The surface of Mars is dotted with dry riverbeds, deltas and lake beds, providing scientists with ample evidence that water was once abundant on the surface of this barren planet. However, about 3.5 billion years ago, a sudden climate change took water away from the surface of Mars. The cause of the rapid drying is not clear, but scientists think it could be due to a sudden loss of the Earth’s magnetic field, an asteroid impact, or the impact of ancient microbial life on the planet due to climate change.

Finding a suitable explanation and figuring out where the water went has become a key question. To look inside the planet for clues, the researchers behind this new study used data collected by NASA’s InSight lander, a robotic seismology laboratory that studied the interior of the Red Planet from 2018 to 2022. Thanks to its sensors, InSight was able to record earthquakes of up to magnitude 5 that reverberated on Earth as a result of displacements caused by meteorite impacts and volcanic activity. By feeding this data into mathematical models similar to those used on Earth to look for aquifers and oil deposits, scientists have mapped Mars’ interior and determined “the thickness of the crust, the depth of the core, the composition of the crust, and even a little bit about the temperature in the mantle,” Manga said.

A study of the deeper crust has revealed that the crust is likely composed of a patchwork of fragmented igneous rocks, containing more than enough liquid water to fill the Martian ocean. This indicates that billions of years ago, water did not escape into space, but instead trickled down into the Earth’s crust. Currently, reaching the secret ocean is far beyond the technological capabilities of humanity (the deepest hole ever drilled on Earth, the Kola Superdeep Well, only 12.2 kilometers into the Earth’s surface). Still, it is not the only place where scientists are looking for life on Mars.

In fact, the rover Perseverance, which has been exploring the surface of Jezero Crater since 2021 for geological samples, may have already collected samples of Martian dust and even evidence of early life. NASA initially planned to launch a sample return mission sometime in 2026, but budget constraints pushed that date back to 2040. The agency is now inviting proposals from private companies to accelerate the mission schedule.