Researchers at Rice University have a new idea about ancient lakes on Mars: they may not have needed a warm climate to exist. Instead, seasonal thin ice could have covered these lakes, slowing evaporation and helping water stay liquid. This fresh perspective could explain why rovers have found well-preserved lake beds and sediment layers on Mars.
Today, Mars is a cold and dry world, but it has clear signs of a wetter past—think expansive lake basins and channels carved by flowing water. Traditionally, scientists struggled to explain how liquid water could last under the thin, frigid atmosphere of early Mars. Short bursts of warmth from impacts or volcanic eruptions couldn’t account for the long-lasting lake features we see today.
The new study suggests a different model, showing how seasonal ice could protect lakes by minimizing heat loss. “I questioned whether those lakes could survive more than a single season in a cold climate,” said Eleanor Moreland, the lead author of the study. She emphasized that the absence of thick ice in ancient lake basins hinted that something else was keeping water stable.
Instead of thick, persistent ice, researchers propose a scenario where thin ice forms in colder seasons. This ice would melt during warmer periods, letting sunlight warm the water. According to Professor Kirsten Siebach, this cycle might have allowed lakes to exist in a stable state for years, yet leave behind little evidence due to the temporary nature of the ice.
To study this hypothesis, the team used a method called Proxy System Modeling, originally designed for reconstructing Earth’s climates. Since Mars lacks tree rings or ice cores, they used minerals and rock layers collected by rovers as stand-ins for climate indicators.
Their new model, named LakeM2ARS, simulates conditions on Mars about 3.6 billion years ago, considering its unique atmosphere and gravity. “Adjusting our Earth-based model for Martian conditions was challenging,” said Professor Sylvia Dee, a co-author. They ran 64 simulations using data from Gale Crater, where NASA’s Curiosity rover has been exploring for years.
Some simulations showed lakes freezing solid and not recovering, while others indicated a thin ice cover that melted in warmer times. This thin layer acted as an insulator, preserving heat and limiting evaporation, which explains the clean condition of ancient lake beds. The researchers plan to apply their model to other Martian regions to check if similar lakes could have thrived elsewhere. If so, it would support the idea that early Mars might have sustained liquid water even in a cold climate.
In recent years, interest in Mars has skyrocketed, driven by missions like SpaceX’s goals for human exploration. The connection between ancient water and potential life forms on Mars has sparked lively discussions on social media platforms, with many users excited about the implications of these findings. As exploration continues, the mysteries of Mars slowly unravel, offering new insights into its past and possibly its future.
For more in-depth understanding of Mars and its lakes, visit NASA’s Curiosity rover page for the latest discoveries.
