Caveman Aliens Could Be Hiding On Mars, Scientists Say

Could these underground bunkers be a long-forgotten refuge for alien life? (Picture: Nasa’s Mars Global Surveyor/Shutterstock)

An ancient Martian system of canyons and valleys could be home to archaic life forms, a ground-breaking scientific paper has found.

Scientists investigating the Red Planet’s mind-boggling cave system believe they’ve discovered something new – eight karst caves sculpted by extinct watercourses.

The paper, published in the highly-respected Astrophysical Journal Letters, suggests these caves could be alien-hunters’ best bet.

Until now, scientists believed that Mars’ skylights – pits in the surface of mars – were formed by volcanic activity.

But data from Nasa’s orbiters suggests there are karst caves – underground bunkers created when a river diverts down through a planet’s surface.

The discovery has got scientists’ chins wagging.

Why do these caves matter?

Conceptual model illustrating water-driven karstic cave development and subsurface habitability potential in Hebrus Valles, Mars. J. A. P. Rodriguez et al. (2012) interpreted the initiation of outflow channels at two large source pits as evidence of groundwater-sourced paleofloods, recognized knick-point retreat as an indicator of collapse into large subsurface voids, noted alignments with possible mud-volcanic structures, and emphasized the absence of downstream outflows?implying that infiltration water and sediments were accommodated within cavities. They further linked the flood source pits to the Hephaestus Fossae trough system, where collapse-related pitted lineations, polygonal troughs, and mud-volcanic chains highlight structural control on water pathways and void formation. Building on this framework, the present study shows that carbonate- and sulfate-bearing lithologies provided soluble substrates (Table 1), with dissolutional processes contributing to cavity enlargement and skylight development (Figures 1, 2, and 3). Our analysis also confirms that no groundwater outflows beyond the sinkhole clusters were identified, consistent with the interpretation of large subsurface voids. Thermal inertia values, higher than unconsolidated dust yet lower than intact rock, together with mineralogical evidence (Figure 4; Tables 2 and 3), reveal heterogeneous layering in which surface dust mantles over more indurated karstic material. Collectively, these geomorphological (Figures 1, 2, and 3), mineralogical and geochemical (Tables 1, 2, and 3), and thermophysical (Figure 4) signatures support the interpretation of the Hebrus skylights as dissolutional karst caves. The potential presence of past water, subsurface ice, and accessible cave resources within these voids further underscores their significance for resource utilization, astrobiological exploration, and broad scientific investigation. These environments offer opportunities to probe Mars? hydrologic and climatic history, unravel dissolution-driven geological processes, and test advanced exploration technologies. As such, the Hebrus skylights emerge as prime targets for future human missions, long-term habitation studies, robotic surveys, advanced robotic dog?based investigations, and high-resolution radar probing of their internal architecture. Such efforts could deliver the first detailed images and 3D maps of extraterrestrial caves, opening unprecedented opportunities for science, exploration, and the search for life beyond Earth. — This conceptual model illustrating water-driven karstic cave development and subsurface habitability potential in Hebrus Valles, Mars. (Picture: Ravi Sharma et al)

Karst caves provide two vital things for sustaining life – shelter from Mars’ intense radioactive rays, and water.

If life on Mars ever existed, it may have needed protection from hostile surface conditions like solar radiation, dust storms, and wild temperature fluctuations.

And we already know that water provides the building blocks for life.

Karst caves may well have provided water and shelter a the same time – roughly 3.5 billion years ago.

The paper’s authors are now urging future Martian ventures to ensure robots head down into these caves.

Geological context of skylight candidates in Hebrus Valles. Skylight candidates (yellow stars) are mapped in relation to pit lines, outflow channels, and sinkholes, revealing their spatial association with fluvial systems. Mapping builds on earlier interpretations (J. A. P. Rodriguez et al. 2012) and was refined in later analyses (D. Sulcanese et al. 2018; R. Sharma et al. 2019). THEMIS daytime infrared image data (P. R. Christensen et al. 2004) has been used for regional mapping. — Photos of the eight skylight candidates in Mars’ Hebrus Valle (Picture: D. Sulcanese et al. 2018; R. Sharma et al. 2019)

They hope they will be able to find ‘preserved biosignatures’ – scientific evidence of past or present life in geological materials like rocks, ice, or minerals.

Scientists believe these are water-formed caves for numerous reasons – especially the composition of its surrounding rock.

Data from Nasa’s Thermal Emission Spectrometer (TES) suggests the presence of carbonates and sulfates – probably caused by water flow dissolving soluble bedrock.

What sort of aliens are we looking for?

Artifical intelligence can help us speculate about alien life, like this artistic interpretation of a what humans could have looked life if they evolved on Mars (Picture: Midjourney/AI)

There is scientific consensus that Mars has had, at a point in its history, the conditions to host organic life.

But what this life looked like, or how complex it may have been, remains hotly discussed,

Some 19^th and 20^th century astronomers believed modern Mars was teeming with intelligent aliens with nefarious plans to invade Earth.

They mistakenly thought dark linear features on Mars were ‘canals’ and that seasonal colour changes were vegetation.

Better telescopes and the development of probes proved them wrong – but scientific discussion of historic life continued.

It led to eminent astronomers like Carl Sagan speculating that, billions of years ago, Martians would have looked like ‘a man dressed up in a turtle suit’ with tentacles protruding out.

Sagan reasoned that ‘the creature’s spindly limbs suit Mars’s low gravity; its glass-like shield blocks ultraviolet radiation’.

FILE - This image provided by NASA, shows a selfie of their Perseverance Mars rover, on July 23, 2024. The image is made up of 62 individual images that were stitched together. (NASA via AP, file) — A selfie taken by the Perseverance Mars rover, on July 23, 2024 (Picture: Nasa/AP)

Nowadays, scientists have lowered their expectations – and are looking for signs of life, either historic or present, of small microbial life.

One of the ‘clearest signs yet’ came in September when Nasa found ‘leopard spots on Mars’ surface’.

Microbes, as they wriggle around on rocks, can create minerals as they gobble up chemicals, leaving behind these mysterious patches.

The findings are noteworthy enough to meet Nasa’s criteria for a sign of ancient life.

And in March, a scientific paper said Nasa’s Curiosity rover had found the largest organic compounds ever seen on the planet.

The material was found inside a 3.7 billion-year-old rock in Yellowknife Bay, which may have once been a habitable freshwater lake.

Onboard tests detected molecules suspected to be remnants of fatty acids, which are produced by living creatures to form cell membranes.

Researchers did however stress that these molecules, though described as organic, could have also formed in chemical reactions that did not involve life.

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