These formations were formed from alternating massive deposits of CO2-ice and water ice, similar to different layers of a pie.
For decades, planetary scientists have wondered how such a formation was possible, as it was long thought that this layering would not be stable for long periods of time.
However, in 2020, astrophysicist Peter Buhler of the Institute of Planetary Science and a team of researchers figured out the dynamics of the formation of cheese-like topography: this was due to changes in the tilt of the axis of Mars, which caused changes in atmospheric pressure, resulting in water and CO2 ice forming alternately.
But they were able to determine the rate at which CO2 and water were deposited over millions of years, about ten times longer than Mars’ orbital cycles.
In a new study, Buhler uses simulations to figure out how frozen deposits of carbon dioxide and water rise and fall over the 100,000-year cycles of Mars’ tilt.
The model allowed the researchers to determine how water and carbon dioxide moved across Mars over the past 510,000 years.
“Mars goes through 100,000-year cycles in which its poles change from tilt toward or away from the Sun,” Buhler said in a press release.
“These changes cause the amount of sunlight falling on each latitudinal band, and therefore the temperature in each band, to change as well.
Water ice moves from warmer to colder regions during these cycles, driving the main long-term global water cycle on Mars.”
Layered deposits of H2O and CO2 ice could provide a record-breaking climate history for Mars, as the south pole ice cap is the only place on the Red Planet where frozen carbon dioxide is stored on the surface all year round.
“This layering is important because it is confirmation of how water and carbon dioxide moved around Mars,” Buhler said.
“The thickness of the water layer tells us how much water vapor was in the Martian atmosphere and how that water vapor moved around the planet.
The layers of carbon dioxide show how much of the atmosphere has frozen on the surface, and therefore how dense or thin the atmosphere of Mars was in the past.”
Buhler explained that knowing the history of Mars’ atmospheric pressure and the presence of water is critical to understanding the underlying processes of Mars’ climate and near-surface geological, chemical, and possibly even biological history.
Contact us: [email protected]