Scientists may have greatly underestimated the number of ancient Martian lakes

Although Mars is currently a frozen desert, scientists have found evidence of ancient lakes that existed there billions of years ago. These ancient lakes may have preserved information about the temperature and life of the ancient Red Planet.

Dr. Joseph Michalsky, geologist at University of Hong Kong (HKU), he said that Scientists may have overestimated the amount of ancient Martian lakes that once existed by meta-analysis of years of satellite data revealing evidence of Lakes on Mars.

Michalsky said, “We know of approximately 500 ancient lakes that were deposited on them Mars, but almost all lakes that we know of are larger than 100 square kilometres. But on Earth, 70% of lakes are smaller than this size, and they occur in cold environments where glaciers have retreated. These small lakes on Mars are difficult to identify by satellite remote sensing, but there are likely many small lakes. It is possible that at least 70% of the lakes on Mars have yet to be discovered.”

Scientists monitor these small lakes on Earth Understanding Climate Change better. Mars’ lost small lakes may hold vital clues to past climates.

The latest study suggests that most of Mars’ lakes date back to 3,500 and 4,000 million years ago, but each lake may only have existed for a limited time period (10,000-100,000 years). This indicates that although ancient Mars was likely fairly cold and dry, it warmed intermittently for short periods.

Michalski added, “Because of the low gravity on Mars and the pervasive fine-grained soil, the lakes on Mars were very murky and probably did not allow light to penetrate deeply, which could pose a challenge to photosynthetic life if they existed.”

Water, nutrients and energy sources for Potential microbial life, including light for photosynthesis, are all found in lakes. Therefore, lakes are the primary areas that Mars rovers, such as the NASA rover, currently on Mars, are exploring for astrobiological purposes.

But not all lakes are created equal. Some lakes may have been more interesting for microbial life than others because some lakes were large, deep, long-lived, and had a wide range of environments, such as hydrothermal systems that would have led to the formation of simple life. From this point of view, it might make sense to target large, ancient, and ecologically diverse lakes for future exploration.

Dr. David Baker, an ecologist in the School of Biological Sciences at the University of Hong Kong, is well versed in the microbial systems on Earth in lakes, He saidAnd the “Earth hosts many environments that could act as analogues for other planets. From the harsh terrain of Svalbard to the depths of Mono Lake – we can determine how to design tools to detect life elsewhere here at home. Most of these tools are aimed at discovering the remains and remains of microbial life.”

Journal reference:

  1. Michalski, JR, Goudge, TA, Crowe, SA, et al. Geological diversity and microbiological potential of lakes on Mars. Nat Astron (2022). DOI: 10.1038 / s41550-022-01743-7