The possibility of liquid water beneath the Martian surface has been reignited by research published late last year. Scientists discovered “seismic discontinuities in the Martian crust,” suggesting the potential presence of liquid water and, consequently, microbial life.
Mars has long fascinated astrobiologists due to its ancient history, similar in some ways to Earth’s, and its relative proximity. This new research strengthens the possibility of microbial life persisting beneath the planet’s desolate surface, as liquid water, a key ingredient for life as we understand it, may exist underground.
Planetary scientist Ikuo Katayama of Hiroshima University, a co-author of the study, noted in a Geological Society of America release that the presence of liquid water on Mars could signify “microbial activity” within the Martian crust.
Various missions, including rovers, landers, and orbiters, are dedicated to unraveling the mysteries of Mars. Data gathered from these missions continually sheds light on the potential for past or present life on the Red Planet. For the past four years, the Perseverance rover has been exploring Jezero Crater, a massive basin that once held a lake billions of years ago. Perseverance has collected intriguing rock samples that NASA plans to bring back to Earth through the Mars Sample Return program.
InSight, a lander deployed in November 2018, played a crucial role in exploring the Martian subsurface. Before its decommissioning in December 2022, InSight detected over 1,300 marsquakes and transmitted nearly 7,000 images of the Martian surface. It also listened for seismic activity and gathered data on wind and dust devils.
The seismic data collected by InSight revealed boundaries approximately 6.2 miles (10 kilometers) and 12.4 miles (20 kilometers) below the surface. Initially, these boundaries were interpreted as changes in rock porosity. However, the study’s authors propose that these boundaries could represent water-filled cracks in the Martian subsurface.
The research team analyzed how different seismic waves on Mars travel through similar rock formations in Sweden. Their experiments demonstrated significant variations in seismic velocities through dry, wet, and frozen samples. This suggests that the observed boundaries at different Martian depths could indicate a transition from dry to wet rock, thereby supporting the presence of liquid water.
While previous studies have suggested the existence of water on ancient Mars billions of years ago, Katayama emphasized that their model indicates the presence of liquid water on present-day Mars. Unfortunately, InSight’s digging tool, the “Martian mole,” was unable to penetrate the surface deeply, hindering NASA’s efforts to fully understand the planet’s internal processes.
The Mars Sample Return mission promises invaluable insights into whether life once existed on Mars. However, given the latest findings, exploring the potential for present-day liquid water may require different approaches, potentially involving deeper subsurface exploration. The quest to understand Mars and its potential for life continues.
