Subsurface Oceans on Mars? NASA’s InSight Uncovers Vast Reservoir of Liquid Water

Geophysicists using seismic data from NASA’s Insight lander have discovered a significant underground water reservoir on Mars, potentially enough to have once filled ancient oceans.

This reservoir, trapped within the mid-crust of Mars, suggests that the red planet’s water did not entirely escape into space but was absorbed into its crust, altering previous theories about Martian aridity and possibly providing a habitat that could support life.

Using seismic activity to probe the interior of Mars, geophysicists have found evidence for a large underground reservoir of liquid water — enough to fill oceans on the planet’s surface.

The data from NASA’s Insight lander allowed the scientists to estimate that the amount of groundwater could cover the entire planet to a depth of between 1 and 2 kilometers, or about a mile.

While that’s good news for those tracking the fate of water on the planet after its oceans disappeared more than 3 billion years ago, the reservoir won’t be of much use to anyone trying to tap into it to supply a future Mars colony. It’s located in tiny cracks and pores in rock in the middle of the Martian crust, between 11.5 and 20 kilometers below the surface. Even on Earth, drilling a hole a kilometer deep is a challenge.