Scientists Figured Out Why Mars’ South Pole Looks Like Swiss Cheese

In stark contrast to the rest of the planet's rusty-red surface, Mars' south pole is covered in bizarre, Swiss cheese-like formations.

While scientists have known for a few years now what those formations are made of — layers of frozen carbon dioxide and frozen water that have been deposited over many years — researchers have had a difficult time tracing how the formations developed and transformed over shorter periods of time.

Now, as detailed in a study published in the journal Geophysical Research Letters, planetary scientist Peter Buhler of the Planetary Science Institute in Tucson, Arizona, presented a model that maps a 510,000-year climate history of how the planet's fantastical Swiss cheese formation changed in accordance to the planet's orbital polar tilts — an "essential step" for understanding our neighboring planet's water cycle.

"Mars experiences 100,000-year cycles in which its poles vary from tilting more toward or away from the Sun," Buhler said in a press release. "These variations cause the amount of sunlight shining on each latitude band, and thus the temperature of each band, to cycle, too."

"Water ice moves from warmer to colder regions during these cycles," he added, "driving Mars' basic long-term global water cycle."

In the study, Buhler utilized a numerical model "to simulate the build-up of the layers over time." He then ran that model "approximately one billion times," until he was finally able to statistically determine which specific configuration of water deposition best matched the Swiss cheese layers present on the planet today.

The research could give us deep insights into the ancient history of Mars.

"The water layer thicknesses tell us how much water vapor has been in Mars' atmosphere and how that water vapor has moved around the globe," he explained. "The carbon dioxide layers tell us the history of how much of the atmosphere froze onto the ground, and thus how thick or thin Mars' atmosphere was in the past."

But understanding the planet's climate patterns isn't just an essential part of understanding how our neighboring planet came to be. If human beings were to ever colonize Mars, understanding its atmosphere and water cycle will be key to our survival.

"The history of Mars' atmospheric pressure and availability of water are critical information for understanding the basic workings of Mars' climate and near-surface geologic, chemical, and perhaps even biologic history," Buhler said in the press release.

"Specifically, the results of this work provide a major step forward for deciphering the basic workings of Mars' water cycle," he continued, adding that the "availability of near-surface water sources is critical for enabling near-surface life as we know it."

More on Mars: NASA Rover Snaps Amazing View of Sunset on Mars