Mars shifts could help explain the mystery lines seen on the surface of the Red Planet, a new study finds.
For years, scientists analyzing the surface of Mars have found clusters of dark, narrow lines that appear seasonally on slopes in the warmer regions against the sun. Previous research has suggested that these enigmatic dark stripes, called repetitive slope lines (RSL), are signs that salt water flows regularly on the Red Planet during the hottest seasons.
Recent missions to Mars have revealed that the planet does have large subterranean soils lower ice. Previous work has suggested that warmer temperatures during Mars spring and summer may help generate salt brines that can remain liquid in the cold, thin air of the Red Planet for at least some time.
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However, geologists have discovered problems with the concept of brine caused by RSL, said lead author Janice Bishop, a planetary scientist at the SETI (Search for Extraterrestrial Intelligence) Institute and NASA Ames Research Center, both in Silicon Valley, California. discover. For example, the angle of inclination where RSL occurs and the features around where it begins “largely do not correspond to a fluid flow process,” she told Space.com.
Now Bishop and her colleagues suggest that chemical reactions could make the Martian surface vulnerable to landslides that RSL can explain.
“Although the surface of Mars today is dry and hard and cold and dominated by wind and abrasion, below the surface microscale interactions of salts with small ice and liquid water particles can occur today,” Bishop said.
The scientists focused on chemical reactions between sulfate minerals such as gypsum with chloride salts, of which table salt is one variety. “On Earth, the interaction between gypsum and chloride salts caused collapse of parts of caves, sinkholes in soft sediments near salt lakes and dams, and uplift of roads,” Bishop said.
The researchers speculated that similar interactions could occur on Mars, although the cold and dry conditions there would delay these reactions. “I’m very excited about the prospect of active surface chemistry on Mars, although it’s slow,” Bishop said.
In the new study, the scientists performed laboratory experiments on mixtures of sulfates, chloride salts, small ice particles and volcanic ash similar to Martian soil. They froze and thawed such mixtures at the low temperatures found on the Red Planet.
The researchers found that thin films formed with sludge water on the surfaces of mineral grains. They suggested that these films could expand and contract over time, leading to revolutions and contractions below the Martian surface. Bishop explains that wind and dust on these unstable surfaces can cause landslides and produce the lines on the Red Planet.
The scientists noted that surface missions on Mars to recent RSL sites could help test their model in the future. They set out their findings today (February 3) online in the journal Science Advances.
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