Research by the University of Edinburgh could make the search for life on Mars more effective,media have reported. Astrobiologist Sean McMahon used a technique called “chemical horticulture” to prove that some ancient fossils may not be the remains of living organisms, but rather natural mineral deposits. This could allow future explorers to look for more promising ways to find signs of life on the Red Planet.
Based on scientists’ knowledge of Mars and its ancient history, the most likely evidence of life is the existence of fossils of individual microbes or their habitats. These are often presented in geological records in the form of mineral structures that show branched non-crystalline structures, hollow and circular cross-sections, stratifications, and other clues.
However, according to McMahon, there are some tubes and filaments that look like organisms, but are actually produced by very simple chemical reactions involving iron-rich minerals. In a laboratory environment, McMahon mixes iron-rich particles with alkaline liquids containing silicates or carbonates. These tiny, complex structures have very similar shapes and chemical compositions to the iron-rich structures found in martian-like rocks found on Earth.
This “chemical horticultural” method can also be found in places such as hydrothermal vents on the sea floor. The question now is whether it is possible to determine whether some fossils are chemical, not biological.
“Although hundreds of years of research has been done on these chemical reactions, they have not been shown to mimic these tiny iron-rich structures in rocks,” Says McMahon. These results require a retest of many examples of the ancient real world to see if they are more likely to be fossils or non-biological deposits. “
The study was published in the Proceedings of the Royal Society B.