The possibility of alien life on Mars is a topic that has captivated astronomers for decades.
Despite the scientific community’s best efforts, however, no proof of past or present life has been found on Mars.
Still, that doesn’t necessarily mean it’s not there, many experts have concluded.
There may be several ways that evidence of alien life on Mars could be evading us.
Life could be hiding under the surface
One recent study has indicated that we need to look deeper under Mars’ surface to find traces of life.
That’s because any evidence of amino acids left over from a time when Mars may have been habitable is likely buried at least 6.6 feet under the ground.
Scientists look for amino acids due to their role in forming life as we know it, per the Scripps Research Institute.
Amino acids, which can be created by life and by non-biological chemistry, are a key component in building life-essential proteins.
And because Mars lacks a magnetic field, its surface is subject to a lot of cosmic radiation that destroys amino acids.
“Our results suggest that amino acids are destroyed by cosmic rays in the Martian surface rocks and regolith at much faster rates than previously thought,” said Alexander Pavlov of NASA’s Goddard Space Flight Center in Greenbelt, Maryland.
“Current Mars rover missions drill down to about two inches (around five centimeters). At those depths, it would take only 20 million years to destroy amino acids completely.”
In light of this new research, a new strategy is required when drilling shallow surfaces with rovers like Perservenace or Curiosity.
Life may exist in ways we don’t yet recognize
Nasa scientist Dr. Moogega Cooper discussed with Talks at Google in April about life on Mars.
When asked whether she thought Mars has or once had life, Cooper’s answer was positive.
She said: “Did water used to exist on Mars? Yes. Does Mars have some interesting chemistry that could have potentially harbored or sustained life? Yes.”
For these reasons alone, Cooper implies that we can’t rule out that life once existed on the Red Planet.
Nasa also hasn’t completely ruled out that there is life on Mars or other planets.
It may just be life that we don’t yet understand.
Cooper notes that microbes on Earth can exist in extremely harsh environments and the same could be said for Mars.
If we do find life, Cooper’s next job would be to make sure that Earth is safe when a sample of it is returned here.
She explained to Talks at Google: “One day we hope to bring samples back to our own planet and you have to have that same consideration.