Readings Show Evidence of Huge Ocean Under Mars' Surface

Yahoo

18-03-2025

Researchers have found new evidence for a massive subsurface ocean on Mars, again raising the possibility of microbial life lurking deep below the Martian surface.
As detailed in a paper in the journal Geology, Research Institute for Marine Geodynamics scientist Yuya Akamatsu and Hiroshima University associate professor Ikuo Katayama examined data collected by NASA's InSight Mars lander, which touched down on the Red Planet in 2018.
"Many studies suggest the presence of water on ancient Mars billions of years ago," said Katayama in a statement, "but our model indicates the presence of liquid water on present-day Mars."
The InSight lander's Seismic Experiment for the Interior Structure (SEIS) instrument observed seismic waves generated by Marsquakes and meteorite impacts to create a map of the planet's interior.
P-waves and S-waves, in particular, can allow scientists to determine the type of rocks lurking below, as well as potential composition changes.
According to InSight's data, discrepancies in seismic velocity of these waves showed up at depths of 6.2 and 12.4 miles, suggesting the existence of "sharp transitions in the porosity (the percentage of open space in a rock) or chemical composition of the Martian interior," according to the statement.
The researchers hypothesized that these boundaries could indicate the presence of water-filled cracks. To test their theory, they scanned P- and S-waves from dry, wet, and frozen samples of a Martian rock analog, in the form of diabase rocks from Sweden.
They found that the seismic velocities observed by the InSight lander most closely resembled transitions from dry to wet rock, suggesting huge caches of subsurface water on Mars. That's in contrast to previous research, which determined that these transitions were likely changes from porous to solid rock at similar depths.
It's yet another exciting piece of evidence suggesting that the Red Planet wasn't just a lush ocean world billions of years ago — it may still be holding plenty of water to this day.
The latest findings corroborate a study published last year, which similarly found that vast quantities of water may still exist under Mars' surface. Using another analysis of seismic data from NASA's InSight lander, the research concluded that "fractured igneous rocks saturated with liquid water best explains the existing data."
"It's certainly true on Earth — deep, deep mines host life, the bottom of the ocean hosts life," said coauthor and UC Berkeley professor of earth and planetary science Michael Manga in a statement at the time. "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."
And Katayama appears to agree with that sentiment.
"If liquid water exists on Mars," he said in a statement, "the presence of microbial activity" is indeed possible.
More on Martian oceans: Scientists Discover Massive Reservoir of Water Hiding on Mars