The frost is present for only a few hours after sunrise
A new study published in Nature Geoscience details a significant discovery of water frost on Mars. The research, conducted by an international team, identified deposits of water ice on the Tharsis Montes volcanoes, a chain of massive peaks located near the Martian equator.
These thin, widespread layers of frost equate to an estimated 150,000 tons of water, which the study suggests undergoes a daily cycle of sublimation and deposition during the Martian cold seasons. This translates to a volume equivalent to roughly 60 Olympic-sized swimming pools.
The data for this discovery originated from over 30,000 images captured by the European Space Agency's ExoMars and Mars Express missions currently orbiting the Red Planet.
"The researchers calculate the frost constitutes at least 150,000 tons of water that swaps between the surface and atmosphere each day during the cold seasons," researchers from Brown University reported in a press release Monday, adding, "That's the equivalent of roughly 60 Olympic-size swimming pools."
According to the study, the frost is present for only a few hours after sunrise before it evaporates in sunlight. The frost is also incredibly thin - likely only one-hundredth of a millimetre thick or about the width of a human hair. Still, it's quite vast. The researchers calculate that frost constitutes at least 150,000 tons of water that swaps between the surface and atmosphere each day during the cold seasons. That's the equivalent of roughly 60 Olympic-size swimming pools.
The European Space Agency's ExoMars and Mars Express missions orbiting the planet captured over 30,000 images of the water frost. According to the study, the images were later analysed by a team of international researchers.
"We thought it was improbable for frost to form around Mars' equator, as the mix of sunshine and thin atmosphere keeps temperatures during the day relatively high at both the surface and mountaintop - unlike what we see on Earth, where you might expect to see frosty peaks," Adomas Valantinas, a postdoctoral fellow at Brown University who led the study, said in a press release.
"What we're seeing may be a remnant of an ancient climate cycle on modern Mars, where you had precipitation and maybe even snowfall on these volcanoes in the past," Valantinas said.
Researchers shared that frost sits in the calderas of the volcanoes, which are large hollows at their summits created during past eruptions. The researchers propose that the way the air circulates above these mountains creates a unique microclimate that allows the thin patches of frost to form.
The researchers believe understanding how the frost formed could allow scientists to reveal more of Mars' remaining secrets, including understanding where water exists and how it moves, as well as understanding the planet's complex atmospheric dynamics, which is essential for future exploration and the search for possible signs of life.