Over the past 300 to 800 million years, the Red Planet has survived six to 20 different glacial cycles, a recent study of glaciers on Mars has revealed.
Our world was covered by glaciers during the last ice age on Earth, 20,000 years ago. Then these glaciers receded to the poles.
These masses of ice left behind stones as evidence, dropping them as they moved to the poles while scraping and cutting trails.
Martian glaciers never left, on the other hand. On the surface of a planet with an average temperature of minus 62 degrees Celsius for more than 300 million years, they have stayed frozen; they have only been coated in rubble.
“All the rocks and sand carried on that ice have remained on the surface,” said study author Joe Levy, a planetary geologist and assistant professor of geology at Colgate University, in a statement. “It’s like putting the ice in a cooler under all those sediments.”
For geologists who have tried to decide whether there was one prolonged Martian ice age that caused their formation or whether they formed over several ice ages spanning millions of years, the glaciers on Mars have long posed a mystery.
This question could be answered by observing the rocks found on the surface of glaciers. Since the rocks erode over time, Levy determined that the discovery of rocks that changed downhill from larger to smaller in sizes would indicate one ice age.
Levy and 10 students at Colgate University in New York state used photographs of 45 glaciers taken by NASA’s Mars Reconnaissance Orbiter, provided that it is not yet possible to visit Mars and study its surface in person.
The high image resolution allowed the researchers to count and determine the size of the rocks. The magnification of the images of the orbiter allowed the team to “see things the size of a dinner table” said Levy.
The researchers counted 60,000 rocks altogether and weighed them. Some of the job, which took two summers to complete, would have cut down on artificial intelligence, but AI can not tell rocks apart from the surface of the glacier.
In several locations on the cold world, ice can be found. This image of the Korolev crater, more than 50 miles wide and packed with water ice, near the north pole, was captured by the European Space Agency’s Mars Express mission.