The earliest known direct evidence of hot water activity on Mars has been found, pointing to the possibility that the planet may have supported habitable environments in its ancient past. Scientists analysed a zircon grain estimated to be 4.45 billion years old, extracted from the Martian meteorite NWA7034, often referred to as "Black Beauty." Geochemical signatures within the grain suggest interactions with water-rich fluids during the planet's formative years.
Hydrothermal Systems and Their Role in Habitability
The research, led by Dr Jack Gillespie from the University of Lausanne and published in the Science Advances journal in collaboration with Curtin University and other institutions, identified chemical markers such as iron, aluminium, yttrium, and sodium in the zircon. These findings imply that hydrothermal systems, driven by magmatic activity, were present on Mars during the pre-Noachian period, predating 4.1 billion years ago. According to the study, these systems could have created conditions favourable to life, mirroring the role hydrothermal systems played in the emergence of life on Earth.
Key Findings and Expert Insights
Dr Aaron Cavosie, from Curtin University's School of Earth and Planetary Sciences, explained to Science Advances that nano-scale geochemical analysis revealed elemental patterns indicating the presence of water during early crust formation on Mars. “Despite the intense meteorite impacts that reshaped the Martian surface, evidence of water during this turbulent era has been preserved,” he stated.
Implications for Mars' Habitability
Previous research on the same zircon grain had confirmed that it had undergone shock deformation from a meteorite impact, making it the only known shocked zircon from Mars. This new study expands on earlier findings by providing direct evidence of water's involvement in the grain's formation.
The international collaboration, supported by Curtin University, the University of Adelaide, and the Swiss National Science Foundation, marks a significant advancement in understanding Mars' early environmental conditions and its potential to have hosted life. The study's insights enhance the scientific understanding of ancient Martian hydrothermal systems and their critical role in creating habitable environments.
