Scientists at the Smithsonian Institution’s Center for Astrophysics (CfA) and Florida Institute of Technology (FIT) may have figured out how to determine if life is lurking deep beneath the surface of Mars, the Moon, and other rocky objects in the universe. The researchers reported their findings in The Astrophysical Journal Letters.
While scientists usually focus their search for life in water on the surface and in the atmosphere of space objects, the research team suggests that the lack of surface water does not preclude the possibility of life elsewhere on a rocky object, such as deep in the subsurface biosphere.
“We examined whether conditions suitable for life could exist deep beneath the surface of rocky objects such as the Moon or Mars, and how scientists can look for traces of past subsurface life on these objects,” explains Dr. Lingam, lead author of the study. “We know this quest will be technically challenging, but not impossible.”
One of the problems for the researchers was to determine the possibility of the existence of water where it, apparently, does not exist. “Surface water requires an atmosphere to maintain a finite pressure, without which liquid water cannot exist. However, water can move to deeper areas, ”adds Lingam. “For example, Mars does not currently have ancient water bodies on the surface, but it is known to have underground lakes”.
The study analyzes the “thickness” of the subsurface region – where, in principle, water and life can exist – of nearby rocky objects. In addition, the question is being studied, whether high pressure in them can completely exclude the existence of life. According to Dr. Avi Loeb, probably not. “Both the Moon and Mars lack an atmosphere that would allow liquid water to exist on their surface, but warmer and more pressurized regions below the surface could allow the chemistry of life to exist in liquid water.”
As for the search for life underground on the Moon and Mars, the researchers note that it will not be easy. We need equipment that is not yet used on any of our neighboring space bodies. “We need to be able to drill tens of kilometers beneath the surface of Mars, and without geological activity exposing these deep layers, we will not be able to explore them,” says Loeb.
However, the problems do not mean that finding life in the subsurface biosphere of a rocky body is impossible even in the near future. “Drilling could be possible in the context of Artemis’ program to establish a sustainable base on the Moon by 2024. You can imagine robots and heavy equipment that will drill deep below the surface of the Moon in search of life, just as we do in search of oil on Earth, ”concludes Loeb, adding that if future missions to Mars and the Moon will discovered subsurface life, the same principles for finding it can be applied to other missions.