If there ever was life on Mars, signs of it could be hiding beneath its icy surface. A recent study from NASA and Penn State University indicates that traces of ancient microbes might still be frozen in Martian ice, potentially discoverable by future missions.
In their research, scientists simulated Martian conditions by freezing E. coli bacteria in two environments: pure water ice and a mix with components found in Martian soil. They cooled these samples to about -60°F (-51°C) and exposed them to radiation levels typical of a 20 million-year period on Mars, extending the analysis to 50 million years.
According to Christopher House, a co-author of the study, this time frame significantly exceeds the age of most surface ice on Mars today, which is often less than 2 million years old. He noted, “If bacteria exist near the surface, we could find them in the future.”
The study revealed that amino acids—essential for life—lasted much longer in pure ice compared to the soil mix. After 50 million years, over 10% of amino acids remained intact in pure ice, while they degraded much faster in the soil blend. This suggests that pure ice might offer better protection against decay.
Interestingly, colder temperatures similar to those on Europa, one of Jupiter’s moons, and Enceladus, a moon of Saturn, further slowed the breakdown of these biological molecules.
Alexander Pavlov, the lead author and a NASA space scientist, emphasized the importance of pure ice as a promising location for finding biological materials on Mars. As they plan future missions, this research will help scientists choose target areas and develop tools to access ice deposits that, while generally younger, could still contain signs of life.
This study highlights the potential for Mars to hold on to past life. Understanding these frozen environments is vital. The insights from this research could reshape our exploration approach, focusing on regions where life may still exist or have existed.
The findings were published on September 12 in the journal Astrobiology. For detailed insights, you can read the full study here.
