According to researchers, Mars may be covered with dozens of different non-living fossil fossils, which make the search for life on the Red Planet difficult. NASA's Perseverance spacecraft lands on Mars in February, and the European Space Agency will launch Rosalind Franklin astronauts in 2022 during an Exomars mission. To delve into life on the planet's past, about 4 billion years ago, when the planet may have been habitable. However, a new paper published November 17 in the Journal of the American Geological Survey points to a potential challenge to these Martian excavations. University geologist Julie Cosmidis "It's really possible that one day we'll see something on Mars that looks biological, but a few years later, with more research, we realize that this object was actually formed by non-biological processes," said Oxford, a British author and co-author of a recent article. To better understand these misleading objects, Cosmidis worked with Sean McMahon, an astronomer at the University of Edinburgh in Scotland, to identify these potentially false biomarkers before astronauts could find them. False Positive
A biological signature can be evidence of the organism itself or any product it produces. By definition, such biological signatures cannot be created by natural physical or chemical processes, and for decades astronomers have identified these biological symbols on Earth to identify potential forms of primitive life in other worlds. But this exploration of biological signatures has a major limitation, and according to McMahon, "we are so skilled at recognizing life that we see it even when it does not exist."
In other words, many things that at first glance They look like biological signatures, they can be created without living conditions. "The range of chemical structures, materials, and compounds that can be produced non-biologically overlaps with those that can be produced biologically," McMahon said. Some phenomena have been debated for decades, and we are still not sure if they are biological or not. In particular, evidence of ancient bacteria and other single-celled organisms, such as algae, can be difficult to identify.
Graphic design of a persistent astronaut searching for the Mars subsurface with the RIMFAX tool Credit: NASA/JPL-Caltech/FFI
For example, in 1996, scientists claimed They found fossils of microscopic creatures in a Martian meteorite. Their discovery was hailed as the first evidence of alien life, and even led to a speech by then-US President Bill Clinton. But further experiments showed that these fossils were completely inanimate and were not made by familiar forms of life.
- NASA astronaut discovered new
organic compounds on Mars On Mars, this confusion will be even more
problematic because scientists will not be able to properly test
the specimens until they are returned to Earth, which means it may
take years to study Martian specimens. "The problem is that these
false biological signatures are often rejected only after further
analysis by different researchers and using different techniques,"
Kasmidis said. But for Mars, we will not have that option for years
after collecting specimens. "Potential biological signatures" There
is a wide variety of potentially false biological signatures on
Mars, has it. One of the best examples is carbon-sulfur biomorphs,
which are small spheres that are similar in size to bacteria and
can spontaneously form reactions between carbon and sulfide. Both
reactants may be abundant on ancient Mars, and as a result, the
resulting biomorphs are well fossilized in the usual Martian rock
formations and are false signs of life.
"And if we find microscopic organic spheres in Martian rocks, they would be very tempting to interpret them as fossil bacteria, but on the other hand, they could very simply be carbon-sulfur biomorphs."
Microscopic view of carbon-sulfur biomorphs made in the laboratory
Credit: Julie Cosmidis
For better analysis, the two researchers reconstructed and attempted previously known false signatures on Mars. Find new specimens that have not yet been identified on Earth. In all, they listed more than a dozen possible fossils in their new article, but there may be more, including on Mars. The researchers hope that their work will help prevent the discovery of error and the resulting frustration that will undermine decades of efforts to search for alien life.
Kasmidis said: It is a natural process in science. "But on a subject that has received as much publicity as the search for life on Mars, there is a risk that misleading results could lead to a general distrust of scientists."
, They say, are fully committed to the search for life on Mars. "We do not want to ignore all the efforts that NASA and the European Space Agency are currently making to find traces of life on Mars, but we want to use these efforts, with the help of researchers on these missions, to better and more consciously interpret objects," Kasmidis said. Let's support it. Created intelligent life on Mars.