Glaciers have advanced and retreated throughout our geological history due to shifts in our climate.
There are carved features on the surface of the glaciers. Scientists have concluded that glaciers on the surface of Mars were stationary because of missing features.
New research by a team of US and French planetary scientists shows that glaciers on Mars did not move as quickly as those on Earth.
The research was conducted by a team of geologists and planetary scientists from the School of Earth and Space Exploration at Arizona State University.
Anna Grau Galofre, an Exploration Fellow with the SESE, was the leader of the study that was conducted at the time she was a PhD student.
The study titled "Valley Networks and the Record of Glaciation on Ancient Mars" was recently published.
A glacier is a large, perennial collection of ice, snow, rock, and water that starts on land and moves downslope under the influence of its own weight and gravity, according to the US Geological Survey.
meltwater gathering below the ice sheet lubricating its passage down across the landscape is the key word here. Glaciers have retreated and left boulders and debris in their wake on Earth.
Grau Galofre and her colleagues modeled how Martian gravity would affect the feedback between how fast an ice sheet moves and how much water escapes below it. Under-ice channels that would likely persist over time would be caused by faster water drainage.
Ice sheets on Mars likely moved and eroded the ground under them at an extremely slow rate compared to what happens on Earth.
Scientists have found evidence that suggests there was activity on Mars in the past. The ridges are made of sand and gravel and could be the result of subglacial channels.
In a recent AGUnews press release, Grau Galofre said.
"Ice is incredibly non-linear. The feedbacks relating glacial motion, glacial drainage, and glacial erosion would result in fundamentally different landscapes related to the presence of water under former ice sheets on Earth and Mars.
Whereas on Earth you would get drumlins, lineations, scouring marks and moraines, on Mars you would tend to get channels and esker ridges under an ice sheet of exactly the same characteristics."
Grau Galofre and her colleagues modeled the dynamics of two ice sheets on Earth and Mars in order to determine if Mars experienced glaciers in the past.
The physical framework and ice flow dynamics that describe water drainage under Earth's sheets were adapted to Mars.
They learned how subglacial drainage would evolve on Mars, how it would affect the glaciers, and how it would cause erosion.
The findings show that glaciers on Earth are not as efficient as glaciers on Mars. This would prevent lubrication at the base of the ice sheets which would lead to faster sliding rates.
Their study shows that lineated landforms on Earth would not have been developed on Mars.
Said GrauGalofre.
"Going from an early Mars with presence of surface liquid water, extensive ice sheets and volcanism into the global cryosphere that Mars currently is, the interaction between ice masses and basal water must have occurred at some point.
It is just very hard to believe that throughout 4 billion years of planetary history, Mars never developed the conditions to grow ice sheets with presence of subglacial water, since it is a planet with extensive water inventory, large topographic variations, presence of both liquid and frozen water, volcanism, [and is] situated further from the Sun than Earth."
The work has implications for the possibility of life on Mars and whether that life could survive the transition to a global cryosphere we see today.
The authors say that an ice sheet could provide a steady water supply, protection, and stability to any subglacial bodies of water where life could have arisen. In the absence of a magnetic field, they would protect against solar and Cosmic Radiation.
These findings are part of a growing body of evidence that supports the existence of life on Mars.
It also shows that missions like Perseverance and Curiosity are looking in the right places.
When Mars was warm and wet, there were life forms that emerged from the glaciers. As the planet became colder and desiccated, it might have continued.
It is possible that as this transition progressed and much of Mars' surface water retreated underground, there could be life on the surface.
Future missions could be the ones that find evidence of present-day life on Mars.
This article was published in the past. The original article is worth a read.
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