by (CNN) The remains of a glacier have been found near Mars’ equator, suggesting that some form of water may still exist in a region on the red planet where humans may one day land.
The ice mass is gone, but scientists have discovered telltale remnants among other mineral deposits near Mars’ equatorial. The deposits there mostly contain bright sulphate salts.
As scientists looked closer, they recognized the features of a glacier, including ridges called moraines — debris deposited or pushed by a moving glacier. The research team also discovered fissure fields, or deep wedge-shaped openings, that form inside glaciers.
The findings were shared Wednesday at the 54th Lunar and Planetary Science Conference in The Woodlands, Texas.
“What we found is not ice, but a salt deposit with the detailed morphological features of a glacier,” said the study’s lead author, Dr. Pascal Lee, a senior planetary scientist at the SETI Institute and the Mars Institute, in a statement.
“What we think happened here is that salt formed on a glacier while preserving the shape of the ice underneath, down to details like crevasses and moraine bands.”
Researchers believe the glacier was 3.7 miles (6 kilometers) long and 2.5 miles (about 4 kilometers) wide, with a height ranging from 0.8 to 1.1 miles (1.3 to 1.7 kilometers). ).
Volcanic activity creates a protective layer
Scientists have an idea of how the glacier imprint was formed based on evidence of volcanic material in the area. When mixtures of volcanic ash, lava, and volcanic glass called pumice react with water, a hard, crusty layer of salt can form.
This annotated image shows all the details of where the glacier once existed.
“This region of Mars has a history of volcanic activity. And where some of the volcanic materials came into contact with glacial ice, chemical reactions would have taken place at the interface between the two to form a hardened layer of sulfate salts,” said study co-author Sourabh Shubham, a PhD student in geology at the University of Maryland, College Park, in a statement.
“This is the most likely explanation for the hydrated and hydroxylated sulfates we observe in this light-toned deposit.”
Geologically young surface ice near the equator
The volcanic material likely eroded over time, revealing the salt layer that had captured an imprint of glacial ice and its distinctive features, said study co-author John Schutt, a geologist at the Mars Institute and an ice field guide in the Arctic and Antarctic.
Mars has a thin atmosphere that allows space rocks to periodically collide with the planet’s surface. But the glacier’s fine, detailed features remain largely undisturbed in the salt deposit, leading researchers to believe it is relatively “young.”
The study’s authors said they believe the glacier existed during the Martian-Amazon geological period, which began 2.9 billion years ago and is still ongoing.
A map shows where the glacial remains were found near the Martian equator.
“We have known of glacial activity on Mars in many places, including in the more recent past near the equator. And we’ve known about recent glacial activity on Mars, but so far only at higher latitudes,” Lee said. “A relatively recent relict glacier at this location tells us that Mars has had surface ice very recently, even near the equator, which is new.”
The researchers do not know whether there is still ice under the deposit.
“Water ice is currently not stable on the surface of Mars near the equator at these altitudes,” Lee said. “Therefore, it is not surprising that we do not discover any water ice on the surface. It is possible that all of the glacier’s water ice has now sublimated. However, there is also the possibility that part of it is still protected at a shallow depth.” under the sulphate salts.”
Potential for flat ice pockets
During the study, the team also examined ancient ice islands, known as salars, in Bolivia’s Altiplano salt flats in South America. Salt blankets have protected ancient glacial ice from melting or evaporating, leading researchers to believe a similar scenario may have occurred on Mars.
Details of the glacier can be seen in this high-resolution image of the feature.
Next, the researchers want to determine whether there is any ice left from the glacier and, if so, how much there is at shallow depths beneath the salt deposits. If this particular salt deposit protects the ice, it’s possible that other ice pockets exist nearby.
Orbiters orbiting the planet have shown deposits of ice on Mars’ cold poles, but if water exists in some form in the warmer equatorial lower latitudes, it could have implications for our understanding of the Red Planet’s history and potential habitability — and on the future exploration by humans.
“The desire to land humans in a place where they could potentially extract water ice from the ground has prompted mission planners to consider locations at higher latitudes,” Lee said. “But the latter environments are usually colder and more challenging for humans and robots. If there were equatorial locations where ice could be found at shallower depths, then we would have the best of both environments: warmer conditions for human exploration and still have access to ice.”
