Meteors show that they will be habitable as long as there is water below the surface of Mars. Deep down Mars, radioactive elements break down water molecules and make materials that can feed life beneath the surface of Mars. This process, known as radiolysis, has stored bacteria for millions and billions of years in waterlogged cracks in the Earth’s rocks. Now a study published in the journal Astrobiology claims that radiation can also support microbial life beneath the surface of Mars.
Dust storms, cosmic rays and solar winds have destroyed the surface of the Red Planet. But some species can take refuge below the surface. According to Jesse Tarnas, a planetary scientist at NASA’s Jet Propulsion Laboratory and the lead author of the article above, “the environment on Mars that has the highest chance of being habitable is its lower surface.” Examining Mars’ subsurface can help scientists determine whether life survives there – and the best examples of Martian subsurface available to us are meteorites that hit Earth.
Tarnas et al. Studied the particle size, mineral composition, and radioactive elements in Martian meteorites and estimated the porosity of the Martian crust using data from satellites and astronauts. They incorporated these properties into a computer model for radionuclide simulation to see how effectively the process could produce sulfate and hydrogen gas – chemicals that could support the metabolism of subsurface bacteria. The researchers report that if there was water beneath the surface of Mars, the irradiation process could have kept microbes alive there for billions of years – and it probably still is.
Scientists have studied Martian radiation in the past, but this is the first estimate using Martian rocks to estimate their habitability below the planet’s surface. Tarnas and his colleagues measured the potential richness of life beneath the surface of Mars and concluded that millions of microbes could live on one kilogram of rock (geobiologists have found similar densities in the underground).
The most habitable specimen tested is a meteorite composed of a rock called “Regolith Breccia”. “The rocks are thought to have originated in the heights south of Mars, which is the oldest surface on the planet,” says Tarans.
Underwater life needs water – and according to Lujendra Ojha, a planetary scientist at Rutgers University, who did not play a role in the study, it is unclear whether water is under the surface of Mars. . The next important step can be to determine if there is news of water there, and this research will be a stimulus for the search for subsurface water. “Where there is groundwater, there can be life,” says Oja.