The debate about water and lakes on Mars is becoming more and more interesting

Scientists have been arguing for years about mysterious radar scans of Mars’ south pole. Do they reveal underground lakes of liquid water? or something else? And two new papers this week have added more intrigue to the controversy.

In 2018, a team of Italian scientists claimed to have Discover a subglacial lake near the south pole of Mars Using radar data from the Mars Express satellite. This discovery was met with skepticism, with others Scientists suggest alternatives such as clay blocks which can produce the same reversal patterns. It’s an intense debate, because of the effects of water on life. While most scientists agree that Mars It was too wetLooks like the H2O you left is so all the ice.

The controversy was reignited this week with new evidence from NASA’s Mars Global Surveyor satellite that supports the liquid water hypothesis. Radar signals from the 2018 study indicated an area 12 miles (20 kilometers) wide about a mile below the surface, which the researchers interpreted as a subglacial lake or patch of liquid water. In order to confirm this interpretation, a different team examined satellite data of the surface topography of the same area. their analysis, published This week in Nature Astronomy, he revealed a 6 to 15-mile (10-15 kilometer) ripple consisting of a depression and a corresponding high area, which are similar to ripples over subglacial lakes here on Earth.

The team then ran a computer simulation of the ice flow corresponding to conditions on Mars, and the simulation produced ripples of similar size and shape to those observed on the surface of the Martian ice cap. The study indicates that there is indeed an accumulation of liquid water under the planet’s south polar ice cap. “Combining the new topographic evidence with the results of our computer model and radar data makes it likely that there is at least one region of subglacial liquid water on Mars today,” Neil Arnold, a researcher at the Scott Polar Institute for Research in Cambridge, said the study’s lead author in a statement. .

But a separate new paper notes that the liquid water radar data was in fact the result of the interaction between different geologic layers on Mars, producing a reflection pattern that could have been misinterpreted as liquid water. who – which studyalso published this week in Nature Astronomy, offers an alternative explanation for the 2018 discovery. The team behind this study created simulations of layers made up of four materials — atmosphere, water ice, glacial carbon dioxide, and basalt — and measured the layers’ interaction with electromagnetic radiation during passing through it.

They found that, depending on the thickness of the layers and how far apart they were, they produced reflections similar to those observed in the 2018 radar data. “On Earth, bright reflections are often an indicator of liquid water, even buried in lakes like Lake Vostok. [under the surface of the East Antarctic Ice Sheet]Dan Lalish, a research associate at the Cornell Center for Astrophysics and Planetary Science and lead author of the study, said in statement. “But on Mars, the prevailing opinion was that it must be too cold for similar lakes to form.”

“None of the work we’ve done refutes the possibility that liquid water is there,” he added. We only think that the interference hypothesis is more consistent with the other observations. I’m not sure that anything less than training can prove either side of this debate categorically right or wrong.”

Temperatures The surface temperature of Mars can drop to about -220 degrees Fahrenheit (-140 degrees Celsius). These frigid conditions constitute the main argument against any liquid water flowing on the Red Planet. But the researchers behind the latest pro-water study argue that geothermal heat from within the planet could be enough to keep the water in liquid form.

Water is a major component of life on Earth, but that does not necessarily mean that our sacred juice of life may sprout life forms elsewhere in the universe. The controversy over water has implications for future crewed missions to Mars, especially if we ever want to establish a permanent presence there.

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