Radiation = Life on Mars?

When you think of radiation, life isn’t the first thing that comes to mind. However, deep below the surface, radioactive elements help to disintegrate water molecules. This in turn creates fuel that can be utilized by subterranean life. This process is known as radiolysis and has helped life below Earth’s surface survive for billions of years. Through radiolysis, life has been able to survive in the most extreme conditions. Recently, a group of astrobiologists published a theory that radiolysis may be occurring on Mars and could have powered microbial life on Mars.

Image of a Crater on Mars's Southern Highlands

Mars's surface is an extreme, barren environment. There are dust storms, cosmic rays, and solar winds that ravage the Red planet’s surface. But astrobiologists are starting to hypothesize that life may have a chance to live below the Martian surface. A team led by Jesse Tarnas, a planetary scientist at JPL said that Mar’s subsurface has the best chance of supporting life. To support this theory, the team collected samples from Martian meteorites that have crash-landed on Earth.

Tarnas and his team evaluated multiple Martian meteorites that had fallen on Earth. They looked for the grain sizes, mineral makeup, and the radioactive element abundance in the meteorites. Additionally, the team created simulations of Mars to estimate the porosity of Mars’s crust. By gathering all of this data, the team was able to create a model that simulated radiolysis to see how efficiently it would produce hydrogen gas and sulfates: chemical ingredients that support microbial life. From the study, the team concluded that if there was any presence of water, radiolysis could have supported microbial life below the Martian surface for billions of years. Cherry on top - the simulation showed that there would still be microbial life today. 

Radiolysis on Mars

This isn’t the first time that radiolysis has been used to see if there could be life on Mars. There have been previous experiments, but they never used Martian rocks  to determine whether it was possible (Instead, they just used simulations). Tarnas and his team estimated that in the most habitable rock sample, the regolith breccia, which originate from the southern Highlands of Mars, as many as one million microbes could exist in one kilogram of rock (This is similar to measurements on Earth, which is insane!). 

If in the near future, Perseverance or some other rover finds even the smallest hint of underground water on Mars, it would show that life on Mars is bound to exist. Of course, this would mean our neighbors aren’t all that we thought they would be with green skin, beady eyes, and big heads, but it would show that we truly aren’t alone.

Render of InSight Drilling on Mars

Sources:

Ogasa, Nikk. “Martian Crust Could Sustain Life through Radiation.” Space.com, Space, 15 Aug. 2021, www.space.com/martian-crust-could-sustain-life-through-radiation. 

Weisberger, Mindy. “Could Life on Mars Be Lurking Deep Underground?” LiveScience, Purch, 16 Dec. 2018, www.livescience.com/64318-mars-life-deep-biosphere.html. 

Wilson, Eric H., et al. “Perchlorate Formation on Mars through Surface RADIOLYSIS‐INITIATED ATMOSPHERIC Chemistry: A Potential Mechanism.” AGU Journals, John Wiley & Sons, Ltd, 25 Aug. 2016, agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2016JE005078.