Is there life on Mars? Scientists have been searching for the answer to this question for a long time. Although no concrete evidence has been found yet, a recent study by NASA has increased curiosity. The US space agency suggests that microbes may find a potential home beneath frozen water on the Red Planet’s surface.
Based on computer modeling, the study authors discovered that the amount of sunlight penetrating water ice may be sufficient to trigger photosynthesis in the shallow pools of meltwater beneath the surface of that ice.
The process of photosynthesis is used by plants and other organisms to convert light energy into chemical energy in their search for food.
On Earth, similar pools of water that form within ice are found to be teeming with life, including algae, fungi, and microscopic cyanobacteria – all of which derive energy from photosynthesis.
What does the study suggest?
NASA’s research was led by Aditya Khullar, who is with the space agency’s Jet Propulsion Laboratory (JPL) in Southern California. The paper was published in Nature Communications Earth and Environment.
“If we’re trying to find life anywhere in the universe today, Martian ice exposures are probably one of the most accessible places we should look,” Khullar said.
Since there are two types of ice on Mars – frozen water and frozen carbon dioxide – the research team looked at water ice as a potential host for life.
Tracing its origin, researchers said that large amounts of it were formed from ice mixed with dust that fell on the surface during a series of Martian ice ages over the past millions of years. It says that the ancient ice, which has now frozen into ice, is still full of dust particles.
Even though these dust particles may obscure light in the deeper layers of the ice, they are important in explaining how subsurface pools of water can form within the ice after exposure to the Sun.
“The dark dust absorbs more sunlight than the surrounding snow, potentially causing the snow to warm and melt up to a few feet below the surface,” NASA says.
The study’s co-author, Phil Christensen of Arizona State University in Tempe, has been studying ice on Mars for the past few decades.
“Dense snow and ice can melt from the inside out, allowing sunlight in that warms it like a greenhouse instead of melting it from the top down,” he said.
Aditya Khullar and his team now hope to recreate some of Mars’ dusty ice in a laboratory so it can be studied in closer detail.