Somewhere in the past, Mars experienced a major climate change. We transform it from a hot and humid environment to the cold and dry environment we know today. Astronomers have long pointed the finger at carbon dioxide (CO .).2). They now consider that another component of the atmosphere may have played a more important role.
Today, it seems that Mars has becomecold and dry; But about 3.5 billion years ago – or a little more – it is It was hot enough for liquid water to flow across the planet’s surface. In 1972, it was the Mariner 9 mission that first revealed landscapes on Mars studded with ancient river basins. For decades, researchers have amassed evidence to support this. However, they still did not know the reason for this shift.
It is generally agreed that the depletion of the Martian atmosphere in . but, (USA) suggests that the transition from a hot, humid planet to a cold, dry planet could be the result of the loss of another component of the atmosphere. Which ? The question remains.(Ko2) has caused this amazing drying of
Researchers studied thousands of photos returned by many In the last years. They analyzed how river courses overlap and how they are altered. All to reconstruct the history of the Red Planet River over the past billions of years. With the idea of combining these analyzes and simulations of climatic conditions. To determine what best corresponds to observations made by instruments that have flown over Mars.
A better target for habitable planets
In the process, the researchers realized a change in the amount of carbon dioxide2 – a , we only know well – in the atmosphere of Mars the climatic conditions of the red planet have not changed sufficiently. In other words, CO2 It does not appear to be the main driver of the wet/dry transition that occurred on Mars. Another major factor could have intervened. He added, “We do not know what this factor is, but it must be present in large quantities to explain the results.” »says Edwin Kite, a geophysicist at the University of Chicago, in A .
The , which is currently roaming the Earth of the Red Planet, could provide additional evidence that would at least help eliminate certain hypotheses. As researchers know, for a planet, maintaining stable – and life-friendly – conditions for millions or even billions of years is no easy feat. Solving the mystery of Mars’ drying up could eventually allow them to target potentially better habitable exoplanets.