Life on Mars? Between myth and scientific reality

Egyptians, Greeks, and Romans had been eyeing Mars since before the invention of the telescope in the 17th century. Each people gave its own unique characteristics and symbols, often associated with blood and war. Because of its unique red color. Mars, the Roman god of violence, war, and youth, takes its name from this planet. This fascination was later greatly amplified through film and literature in the 19th and 20th centuries. It works like this: world war (1898) H.G. Wells or even mars chronicles (1950) Ray Bradbury’s significant contribution to the democratization of Mars In popular culture.

If speculation about the existence of life on Mars actually dates back to the 17th century, the first real exploration of the existence of life on Mars was as follows. Find traces of life On Earth, it only started in the 1970s. NASA Viking Program It was the first American machine to be landed for this purpose. The 2011 Curiosity mission provided new evidence that life may have existed on Mars. The presence of organic compounds and liquid water in the past has revived hopes for the potential for life on Mars. Recently, Rover Perseverance took the search for signs of life one step further. What stage have we reached and what does science currently say on this topic?

Search for life beneath the surface of Mars

February 18, 2021 Perseverance has landed on Mars.. One of its missions will be to collect samples of Martian rocks and soil from habitable sites on Earth. This can be sent back to Earth for researchers to analyze in more detail. Preliminary observations suggest that Jezero Crater (arrival site) once contained liquid water in the form of a lake, which is good news.

However, the presence of water alone is not sufficient to determine whether Mars was once inhabited. That’s what Perseverance is looking for. specific compounds : carbon, hydrocarbon, amino acid or lipid. Finding these organic compounds is essential because they are the building blocks of life as we know it. In July 2023, Perseverance discovered organic molecules in Jezero Crater. At least 2.3 to 2.6 billion years ago ” According to this post published in nature.

With that, curiosity mission (another NASA rover) pursues goals equivalent to Perseverance and will also perform a variety of analytical and environmental measurements. At the end of 2021, this “ A mixture of carbon isotopes was observed in rocks from Gale Crater, which may be a sign of life on Earth. » Shall we read? this item ~ Of geographical country. Again, there is nothing to indicate that these isotopic changes result from biological activity.

Clues and Interpretation: The Challenge of Proof

Analysis of data from these two missions and others (ExoMars, Insight, etc.) leads to the hypothesis that microbial life may exist in the Martian subsoil. These microbial communities are believed to be the result of water contact with rocks from meteorites. But this still needs to be proven,Hypothesis is currently being studied.

Jesse Tarnas, a researcher at the Jet Propulsion Laboratory in the US, explained in a Brown University press release: We still don’t know if there was life beneath the surface of Mars. If so, I think there will be enough energy there to last until today. “. There is nothing explicitly indicating this yet. Today’s Mars was once home to life.

It is important to keep in mind that any biological clues discovered on Mars can be explained by geological or chemical processes. We don’t know the bottom. In reality, we know very little about how Mars works. The scientific community interprets mission results through the prism of current knowledge and, consequently, the theoretical models developed up to that point. Caution is therefore needed and much research is still needed to draw firm conclusions.

The search for life on Mars continues today a huge scientific challenge, researchers constantly oscillate between the hope of new observations and the caution that must remain in interpreting these data. Whether life ever existed or not, improving our knowledge base on Mars will help us better understand the process. that allowed life to exist on Earth. Amy Williams, an astrobiologist at the University of Florida, expands on this particular aspect: “The ancient histories of the two planets have a lot in common, and we wonder why they evolved so differently.” Little green men are not for tomorrow!

• The search for life on Mars continues to advance thanks to the missions of Perseverance and Curiosity.
• There are currently indications that this planet may have hosted life in the past, but nothing has yet been confirmed.
• Interpretation of the collected data must be done with the utmost care by the scientific community.