There is an interesting hypothesis (never proven) for decades by astrobiologists, and it is the one that states that life was formed on Mars much earlier than on Earth, and that in fact it did not form on our planet, but rather ” it migrated “from one neighboring planet to another.
Life has never been proven on Mars, today a giant “fossil”. But perhaps millions of years ago this red planet had geological processes similar to those that make life on Earth possible today and thus was home to life of different natures. Maybe even our own ancestors.
These are mere hypotheses, but they may not be far from the truth, according to NASA’s latest exciting finding: The Curiosity rover has found new organic evidence preserved in rocks on Mars that suggests the planet may have supported ancient life , according to explains in a statement.
Although not necessarily evidence of life itself, these findings are a good sign for future missions exploring the planet’s surface and subsurface.
The new findings boil down to: “resistant” organic molecules in three-billion-year-old sedimentary rocks near the surface, as well as seasonal variations in methane levels in the atmosphere.
Let’s take a closer look at what the new tests consist of and what they imply.
Existence of simple organic molecules
A number of simple organic molecules have been found, such as benzene, propane or thiophene; thiophene is especially important because it has a sulfur molecule in its structure. This reveals that it was part of a much larger and older molecule.
Organic molecules contain carbon and hydrogen, and can also include oxygen, nitrogen, and other elements. While they are commonly associated with life, organic molecules can also be created by non-biological processes and are not necessarily indicators of life, although it is highly likely, as we say, that these simple molecules have one day formed more complex organic molecules.
Methane in cyclical quantities
The next discovery that has been made concerns the atmosphere and a key organic hydrocarbon, methane. The amount of methane is cyclical on Mars, that is, its amount is much higher in summer and decreases in winter. Specifically, in summer there is three times more methane on Mars than in winter. Why?
What could be causing this increase in methane in the Martian summer? Is it life? It may be due to complex geological processes. But it is also possible that living microbes exist under the rocks of Mars.
To determine the origin, it is necessary to do more studies and send more missions. And this, the researchers are very clear.
“These new findings encourage us to stay the course and continue looking for evidence of life,” according to Thomas Zurbuchen, associate administrator for the Science Mission Directorate at NASA Headquarters in Washington. “I am confident that our current and planned missions will unlock even more impressive discoveries on the red planet.”
” Curiosity has not determined the source of the organic molecules,” says Jen Eigenbrode of NASA’s Goddard Space Flight Center in Greenbelt, Maryland, lead author of the scientific paper explaining these findings, published in Science . “Whether it has a record of ancient life, was food for life, or existed in the absence of life, organic matter in Martian materials contains chemical clues about planetary conditions and processes.”
Furthermore, although the surface of Mars is inhospitable today, there is clear evidence that, in the remote past, the Martian climate allowed liquid water , an essential ingredient for life as we know it, to clump together on the surface. Curiosity data reveals that billions of years ago, a lake of water within Gale Crater contained all the ingredients necessary for life, including chemical components and energy sources.
“The Martian surface is exposed to radiation from space. Both radiation and aggressive chemicals break down organic matter,” explains Eigenbrode. “Finding ancient organic molecules in the first two inches of rock that was deposited when Mars may have been habitable bodes well for us to learn the history of organic molecules on Mars with future missions that will go deeper.”
