- Perseverance rover found multiple water activity phases in Mars' Jezero Crater
- Mineral analysis revealed 24 minerals tracing Mars' chemical evolution over time
- Early water was hot and acidic, unsuitable for life with volcanic rock alteration
NASA's Perseverance rover has uncovered remarkable new evidence about Mars watery past, showing that the Jezero Crater once went through several distinct stages of water activity.
These discoveries suggest that the Red Planet may have had environments suitable for life at different times in its ancient history. Using advanced mineral analysis, scientists have pieced together a story of changing water conditions that could have supported tiny forms of life.
The findings, published in the Journal of Geophysical Research, Planets, provide new insight into the dynamic and changing nature of Mars long ago.
Perseverance, which continues its mission to explore Mars, has been studying the Jezero Crater in great detail.
Scientists used a modern analysis technique called the Mineral Identification by Stoichiometry (MIST) algorithm to examine the mineral deposits there. This method, which works with X-ray data from Perseverance's Planetary Instrument for X-ray Lithochemistry (PIXL), helped researchers identify 24 different minerals that trace the chemical evolution of the planet.
Eleanor Moreland, a research student at Rice University and author of the study, explained that minerals found in Jezero Crater indicate that several different phases of liquid water existed there over time.
Each phase had different chemical compositions and temperatures, which influenced the mineral formation process. These findings suggest that water activity in Jezero Crater did not occur just once, but rather underwent multiple phases that could have created favourable conditions for life.
The study shows that the crater's mineral composition changed over time from hot and acidic fluids to more balanced and alkaline water, conditions considered more suitable for life.
This gradual change reflects the evolving environment of Mars and the subsequent increased potential for life.
The first phase of water activity in Jezero Crater was very harsh. At that time, the water was extremely hot and acidic, making it unsuitable for life.
During this period, minerals like greenalite and hissingerite formed, indicating that volcanic rocks were altered by high-temperature, acidic fluids. These minerals are among the oldest samples identified in the study.
As Mars's atmosphere changed, Jezero's water gradually became less acidic and more balanced, creating somewhat better conditions for life. Minerals like minnesotaite and clinoptilolite were found in this second phase, indicating cooling of the water and changes in its chemical composition.
Such minerals are typically associated with environments where the water's pH level is balanced-meaning this phase was more favourable for life than the first.
The final phase of water activity in Jezero Crater is considered most important for the possibility of life. The water during this time was cool and alkaline, resembling Earth's habitable environment. During this phase, a mineral called sepiolite, which is commonly found in Earth's alkaline environments, formed. The presence of this mineral suggests that this phase was the most widespread and life-friendly water activity on Mars.
