Ancient alien life is most likely to be more than six feet beneath the surface of Mars

Ancient alien life is most likely to be more than six feet beneath the surface of Mars ...

Get your digers ready.

According to a new NASA laboratory investigation, rovers may have to dig about 6.6 feet (two meters) beneath the surface of Mars to discover ancient life evidence as a result of the effects of ionizing radiation on small molecules such as amino acids.

Because they are used by terrestrial life as proteins, the discovery of certain amino acids on Mars would be a good indication that life once existed on the red planet.

The issue is that these are obliterated by cosmic radiation, thus many of the old Martian life may be gone someday.

Destructive cosmic radiations may stifle the search for ancient Martian life.

Researchers from NASA discovered that cosmic radiation destroys amino acids much faster than previously assumed.

"Our findings demonstrate that amino acids are destroyed by cosmic rays in the Martian surface rocks and regolith at much faster rates than previously assumed," said Alexander Pavlov of NASA's Goddard Space Flight Center in Greenbelt, Maryland. "Already Mars rover missions drill down to about two inches (around five centmeters). It would take only 20 million years to destroy amino acids completely."

The term 'only' followed by 20 million years might seem strange, but we're talking huge timescales because to the fact that life would have likely existed on Mars billions of years ago, if Mars had lakes and flowing rivers on its surface.

According to the new findings, missions that cannot drill to deep depths, such as NASA's Perseverance and Curiosity rovers, should modify their sampling methods. "Missions with shallow drill sampling have to look for recently exposed outcrops, e.g., recent microcraters with ages less than 10 million years or the material ejected from such craters," said Pavlov, the lead author of the new study.

Simulating Mars conditions

The team mixed several amino acids in silica, hydrated silica, or silica and perchlorate to simulate the conditions on Mars. They then sealed the samples in test tubes under vacuum conditions to simulate the thin Martian air.

To simulate the effects of cosmic radiation penetrating the Martian surface in real life, these samples were blasted with different levels of gamma radiation. They applied enough radiation to account for up to 80 million years of exposure on the red planet.

Pavlov said his research is the first comprehensive investigation where the destruction (radiolysis) of a wide range of amino acids was studied under a variety of Mars-relevant factors (temperature, water content, perchlorate abundance) and the rates of radiolysis were compared. "It turns out that the addition of silicates and particularly silicates with perchlorates greatly increases the degradation rates of amino acids."

Curiosity's rover recently studied the quantity of organic carbon found in Martian sediments, revealing that it was comparable to some parts of Earth. However, Curiosity and Perseverance may soon modify their approaches to look for more recently discovered samples.

You may also like: