Study Suggests Life Could Thrive Beneath Mars’ Frozen Waters

Life on Mars could potentially exist beneath the planet’s frozen surface, according to a new NASA study. The research suggests that microbes might find refuge in meltwater under the ice, similar to environments found on Earth.

Using computer models, the study shows that photosynthesis could be possible in shallow meltwater pools just below the ice, based on the amount of sunlight that penetrates the surface. On Earth, similar conditions have allowed algae, fungi, and microscopic cyanobacteria to thrive within ice-covered waters, all powered by photosynthesis.

Aditya Khuller, the study’s lead author from NASA’s Jet Propulsion Laboratory in California, emphasized that “Martian ice exposures are likely one of the most accessible places we should explore” for life beyond Earth. The findings have been published in *Communications Earth & Environment*.

Mars has two types of ice: frozen water and frozen carbon dioxide. The research focused on water ice, which formed during several ice ages over the last million years on Mars. Snow mixed with dust settled on the planet’s surface, eventually solidifying into ice containing traces of dust.

The presence of dust particles is key to explaining how meltwater pools could form under the ice. These particles absorb sunlight, causing the surrounding ice to warm up and melt a few feet below the surface. This melting process, however, is questioned by some Mars scientists due to the planet’s thin, dry atmosphere, which they believe prevents ice from melting. Instead, they argue that ice would turn directly into gas on the surface. But the researchers believe the situation could be different beneath the dusty snowpack or glaciers.

Life on Earth can survive in pockets of meltwater created by dust within ice. Windblown dust on Earth’s ice absorbs sunlight, melts the surrounding ice, and creates small cavities where microbial life can thrive. These cavities stop sinking once they reach a depth where the sun’s rays no longer penetrate, yet remain warm enough to maintain meltwater, fostering a stable ecosystem.

“This is a common phenomenon on Earth,” explained Phil Christensen, co-author from Arizona State University. He noted that dense snow and ice can melt from within, acting like a greenhouse, allowing sunlight to warm the ice from the inside rather than melting from the surface down.

The paper proposes that on Mars, dusty ice could allow enough light for photosynthesis as deep as nine feet below the surface. The upper layers of ice would act as a shield, preventing the meltwater from evaporating and offering protection from harmful radiation. This shielding is crucial, as Mars lacks a magnetic field to protect it from solar radiation and cosmic rays.