Scientists say that the old Mars planet had hot weather and rain storms before the planet became ice cold

The climate on Mars between 3 and 4 billion years ago may have been hot enough to withstand major rainstorms and white water before conditions get cold and the planet does not get colder. be more frozen, according to research.

The existence of ancient networks of valleys and lacustrine deposits on the red planet indicates that liquid water was once abundant on the surface. However, scientists could not agree on whether the climate was hot and humid, cold or cold.

But now, the conclusions presented at the Goldschmidt geochemistry conference in Barcelona on Monday by Briony Horgan have cast new light on the ancient climate of Mars, indicating that the red planet had one or more long periods dominated by storms of rain and white water, before surface water. frozen.

"We know that there have been periods of freezing the surface of Mars, we know that there have been periods of free flow of water," Horgan said in a statement. . "But we do not know exactly when these periods were and how long they lasted."

To better understand the ancient climate of the planet, Horgan and his colleagues compared data on the characteristics of Martian mineral deposits – collected by NASA's spacecraft and rovers – with similar information on areas of the Earth considered like analogues of Mars.

"We have never sent unmanned missions to areas of Mars that can show us the oldest rocks, so we need to use earth science to understand the geochemistry of what might be happening. to be there, "said Horgan. "Our study of alteration under radically different climatic conditions, such as the Cascades in Oregon, Hawaii, Iceland and other places on Earth, can show us how the climate affects the patterns of mineral deposition, as we see on Mars. "

"Here on Earth, we find silica deposits in glaciers, characteristics of melting waters," she said. "On Mars, we can identify similar silica deposits in the youngest areas, but we can also see older areas that look like the deep soils of the Earth's warmer climates." There are three or four billion years ago, a slow general trend from hot to cold, with periods of thaw and freezing. "

However, while these results support the idea of ​​this slow warming trend, the climate models of the old Mars are struggling to produce scenarios in which surface water could have remained unfrozen. The reason is that the planet has only received a limited amount of sun heat. This means that scientists may have overlooked some chemical, geological or other factors that may have contributed to warming earlier in the history of the planet.

The warmer conditions increase the possibility that life has developed in early March, according to the researchers. Thus, the latest findings could have important implications in the search for life there.

"We know that the building blocks of life on Earth developed very soon after the formation of the Earth, and that running water is essential to the development of life," said Horgan. "Thus, the evidence we had early, from the water flowing over Mars, will increase the chances that a simple life will have developed around the same time as on Earth." We hope that the mission March 2020 will be able to take a closer look at these minerals, and begin to answer exactly what conditions existed when Mars was still young. "

Scott McLennan, a professor at Stony Brook University in New York who was not involved in the research, praised Horgan's study.

"What is particularly interesting in this work is that he used well understood terrestrial geological processes in areas that are good analogues for Mars," he said. "The results not only make sense from the point of view of developing climate change models for Mars, but they also highlighted a possible mechanism for the formation of the most interesting components, the most more confusing and more non-crystalline, which have been found in all the samples analyzed up to now by Curiosity, vagabond. "