By analyzing a Martian meteorite, scientists from the University of Lausanne (UNIL), with Australian colleagues, discovered traces of water dating back 4.45 billion years. They thus go back to the beginning of the formation of the red planet.
Thanks to observations from Mars rovers and space probes, it has been known for decades that the planet Mars was once home to water, and probably rivers and lakes. However, many questions remain, in particular knowing when this precious liquid appeared in the history of Mars, UNIL said in a press release on Monday.
By analyzing the composition of a mineral – zircon – found in a Martian meteorite, UNIL scientists, with colleagues from Curtin University and the University of Adelaide in Australia, managed to date traces of water in the crust of Mars. According to this study, published in Science Advances, hydrothermal activity dates back 4.45 billion years, or only 100 million years after the formation of the planet.
“Our data suggests that there was water in the crust of Mars at a time comparable to the first traces of water on the Earth’s surface, around 4.4 billion years ago,” comments Jack Gillespie, first author of the study and researcher at the Faculty of Geosciences and the Environment at UNIL.
This discovery provides new elements to understand the planetary evolution of Mars, the processes that took place there and its potential to have hosted life, according to the authors.
A meteorite that says a lot
Scientists have been working on a small piece of the meteorite NWA 7034 “Black Beauty”, discovered in the Sahara in 2011. “Black Beauty” comes from the Martian surface, and was thrown to earth during an impact on Mars there is approximately 5 to 10 million years old. The analysis focused on zircon.
Very resistant, zircon crystals are key tools for dating geological processes. They contain chemical elements making it possible to reconstruct the conditions of its crystallization: the temperature, the interactions with fluids, but also the date. “Zircon contains traces of uranium, an element which acts as a natural clock,” explains Jack Gillespie, quoted in the press release.
The team identified patterns of elements in this unique zircon, including unusual amounts of iron, aluminum and sodium. These elements were incorporated when zircon formed 4.45 billion years ago, and their presence suggests the existence of water during early Martian magmatic activity.
These new discoveries reinforce the hypothesis that the Red Planet may have provided favorable conditions for life at some point in its history. Which would include the presence of nutrient-rich hot springs.
Hydrothermal systems have been essential to the development of life on Earth. These results suggest that Mars also had water, a key ingredient for a habitable environment, during the earliest history of its crust formation.
This article was automatically published. Source: ats
