Eight chasms that lead to subterranean voids were found on Mars — DailyGalaxy
The finding in the Hebrus valley became a true scientific sensation for planetary scientists: caves have been discovered on Mars for the first time, which might have formed not due to volcanism, as previously assumed, but under the influence of water.
Eight deep sinkholes, identified by a Chinese research team, have changed perceptions about the Red Planet’s geological history and where life might have been concealed.
These features significantly broaden the possibilities for forthcoming expeditions, as biosignatures of ancient microorganisms could have been preserved specifically underground. DailyGalaxy reports this.
A New Chapter in Martian Geology
The study, published on October 30, 2025, in The Astrophysical Journal Letters, relies on data from NASA orbital craft, including the now-defunct Mars Global Surveyor.
Analysis of imagery revealed eight circular openings in the northwestern part of Mars, within the Hebrus Valles region. They proved deeper and cleaner in structure than familiar lava tubes: characteristic boulders or raised rims, typically formed after meteor impacts, are absent here.
The authors classified the features as skylights—collapse areas leading into subsurface voids.
The composition of the surrounding rocks is intriguing. Thermal spectrometer TES data revealed carbonates and sulfates—minerals that form through prolonged interaction of water with rock.
This chemical imprint suggests that the surface dissolved due to flows of underground water, creating tunnels and hollows analogous to terrestrial karst landscapes.
Why These Caverns Are Unique
On Earth, karst is a common landform type occurring in areas with layers of soluble rocks like limestone or dolomite. However, such formations had not been documented on Mars until now.
Previously identified caves were either volcanic or linked to tectonic faults. The new category—aqueous karst caves—expands the roster of known Martian geological processes for the first time.
Scientists hypothesize that the formation of these voids occurred millions of years ago, when stable water systems existed on the planet. Gradual rock dissolution formed a network of cavities, covered by upper soil layers.
Such structures could have played a crucial part in preserving organic traces, shielding them from destructive surface factors—radiation, wind erosion, and sharp temperature fluctuations.
Caves as Potential Sanctuaries for Life
It is believed that if life ever existed on Mars, it might have resided underground. The calm microenvironment inside caves offers protection from solar radiation and the extreme climate.
According to EarthSky, scientists allow that microorganisms could have persisted within such karst systems given the presence of water, necessary chemical compounds, and suitable temperatures.
The benefit of these sites is that they represent precise targets for future missions. Instead of a broad search across the planet’s surface, resources can be directed toward targeted investigation of areas where conditions for actual or ancient life seem most probable. Moreover, studying the caves helps to comprehend the extent of Martian water activity and its link to geological processes.
What the Discovery Means for Upcoming Missions
Identifying the first potential karst systems expands comprehension of Martian landscape diversity. For astrobiologists, this signifies an important breakthrough: such structures may hold traces of biological processes that would have been destroyed on the surface.
New challenges emerge for engineers—developing compact robots capable of descending into subsurface cavities and relaying data from hard-to-reach spots. Such craft are viewed as a promising tool for exploring Martian caves.
The scientific community views the finding as evidence that key Martian relief-forming processes were more varied than previously assumed.
It demonstrates that water played a significant role in subterranean systems and could have sustained conditions suitable for primitive life forms.
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