Scientists have made a discovery about Mars that could lead to the discovery of extraterrestrial life.
They identified a 3,000-kilometer-wide plain in the Northern Hemisphere that has the right subsurface conditions to support living organisms.
The region – called Acidalia Planitia – contains just the right levels of water, heat and energy in the soil for alien bacteria to thrive.
The next step is to drill into the surface of Mars to see if life really emerged there.
“(It is) a promising target area for future missions in the search for existing life in the Martian subsurface,” wrote the researchers led by Andrea Butturini of the University of Barcelona.
But researchers would have to dig miles beneath the Red Planet. This would require large crewed missions and technologies that are unlikely to be feasible for years to come.
However, this study brings scientists one step closer to finding definitive evidence of life beyond Earth by targeting a location where microbial life could exist.
Furthermore, it lays the foundation for future studies that could settle an “intense debate” about the presence of methane in the Red Planet’s atmosphere.
A new study shows that alien bacteria may be 4.5 to 8.5 kilometers below the surface of the Martian plain called Acidalia Planitia.
That’s because the alien life forms that researchers think could be living under Acidalia Planitia are methanogens, or methane-producing bacteria.
Methanogens are extremophiles: bacteria that thrive in extreme environmental conditions, such as very high temperatures, ultra-salty water or even high radiation levels.
On Earth, methanogens typically live in swamps and swamps, but they can also be found in the intestines of cows, termites and other herbivores, as well as in dead and decaying organic matter.
These microorganisms are anaerobic, meaning they do not need oxygen to survive. They can also survive without organic nutrients or sunlight.
In 2028, the European Space Agency (ESA) plans to launch their Rosalind Franklin rover, formerly known as the ExoMars rover.
This includes a drill that can dig about two meters into the surface of Mars.
But that’s not nearly deep enough to access the potentially habitable depth Butturini and his colleagues identified.
The surface of Mars is inhospitable due to extremely cold temperatures and low pressure that even extremophiles could not survive.
But beneath the surface, the radioactive decay of elements such as thorium – a radioactive metal – produces heat and chemical energy. Furthermore, water left over from ancient oceans is buried in the Red Planet.
These conditions could provide the ingredients for bacterial life, but probably up to five miles lower.
Butturini, a biogeochemist at the University of Barcelona, and his colleagues used data from Mars orbiters to pinpoint areas where abundant thorium could provide life-sustaining energy.
Methanogens are extremophiles: bacteria that thrive in extreme environmental conditions, such as very high temperatures, ultra-salty water, or even high radiation levels
In 2028, the European Space Agency plans to launch their Rosalind Franklin rover, formerly known as the ExoMars rover.
They then linked this data to the distribution of subsurface ice previously mapped by missions such as China’s Zhurong rover.
This analysis found that the “most robust target area is the mid-latitude southern Acidalia Planitia,” located near an area of clay and carbonate deposits with evidence of groundwater activity.
At this underground location, temperatures are higher than at the surface, averaging between 32 and 50°F.
That means liquid water could be mixed into the soil of Mars. And where there is liquid water, bacterial life can grow.
The findings are currently available on the pre-print server arXivmeaning the study has yet to be reviewed by other scientists.
But the research is already receiving attention from the scientific community because it provides a specific location on which to focus the search for extraterrestrial life.
“The subsurface of the southern Acidalia Planitia is a likely target area for harboring cold-adapted Methanosarcinaceae-like and/or Methanomicrobiaceae-like methanogens,” the study reads.
‘In this region, radiogenic heat-producing elements are most abundant and underground water is likely.’
If the researchers’ theory ultimately proves correct, it would not only lead to the groundbreaking discovery of alien life on Mars, but would also provide indirect evidence for the presence of biologically generated methane in the Martian atmosphere.
Observations of methane in the Martian atmosphere have been reported since 1999, but have always been conflicting. These measurements show highly variable methane concentrations, with global averages ranging from 5 to 33 parts per billion by volume.
In particular, the discrepancy between measurements taken by NASA’s Curiosity rover and the ExoMars Trace Gas Orbiter.
While Curiosity has detected methane in the Martian atmosphere, the ExoMars orbiter has not. This has sparked a heated debate within the scientific community.
Finding methanogens living beneath the surface of Mars would be strong evidence that the Red Planet’s atmosphere does indeed contain methane generated at least in part by microbial processes.
Methanogens produce methane as a byproduct of their metabolism.
Alternatively, atmospheric methane could arise from non-biological processes such as volcanic or hydrothermal activity. Or it could not exist at all.
While this debate is far from settled, identifying locations where microbial life might exist on Mars brings scientists closer to understanding the true composition of the Red Planet’s atmosphere and finding extraterrestrial life.