While Mars may be a dessicated place where water no longer flows, the planet still has glaciers slowly moving across its surface. Previously, it was thought that Martian glaciers were pure ice with a thin cover of rock and dust. But after 20 years of exhaustive research, scientists have concluded that glaciers all over the planet contain more than 80% water ice, meaning they are nearly pure. These findings could alter our understanding of Mars’ climate history and have significant implications for future crewed missions dependent on in-situ resource utilization (ISRU).

Yuval Steinberg, a recent graduate of the Weizmann Institute of Science, led the research team responsible for these findings. He was joined by Oded Aharonson and Isaac Smith, two senior scientists at the Planetary Science Institute (PSI) with faculty appointments at the Weizmann Institute of Science and York University, respectively. The paper detailing their findings, “Physical properties of subsurface water ice deposits in Mars’s Mid-Latitudes from the shallow radar,” recently appeared in the journal Icarus.

The team’s study focused on Lobate Debris Aprons (LDAs), ice-rich landforms found on slopes of massifs, primarily in the mid-latitudes on Mars. Previously, researchers believed that these glaciers were either “rock glaciers” with a water ice content of 30% or composed of near-pure water ice beneath a layer of debris. The team was inspired by past research, which revealed that the study of ice formations on Mars has been somewhat irregular. To address this, the team sought to develop a standardized method for analyzing glaciers based on two key factors.

An artist’s impression of the Mars Reconnaissance Orbiter using its Mars Climate Sounder instrument.Credit: NASA/JPL-CalTech

These included how quickly radar waves pass through them (their dielectric properties) and how quickly energy from radar waves dissipates into them (their loss tangent). Using this method, the team selected five LDAs on Mars that were studied by the SHAllow RADar (SHARAD) instrument aboard the Mars Reconnaissance Orbiter (MRO). This allowed them to draw comparisons between glaciers located all across the planet, which revealed that all had virtually identical properties. As Smith explained in a PSI press release:

Different techniques had been applied by researchers to various sites, and the results could not be easily compared. One of the sites in our study had never been studied, and at two of the five sites we used, only partial analysis had been completed previously. This is important because it tells us that the formation and preservation mechanisms are probably the same everywhere. From that, we can conclude that Mars experienced either one widespread glaciation or multiple glaciations that had similar properties. And, by bringing together these sites and techniques for the first time, we were able to unify our understanding of these types of glaciers.

Using this method, researchers can infer the ratio of rock to ice within, which cannot be done using visual observations of dust and rock-covered glaciers alone. Understanding the minimum purity of Martian glaciers will lead to a better understanding of the processes that form and preserve them, and will help when it comes time to plan for crewed missions. Per NASA’s mission architecture, landing site selection will need to account for the availability of essential resources, such as water ice. Aside from providing crews with a local source of drinking water, this ice can be fashioned into oxygen gas and rocket propellant.

“This study highlights how NASA programs are advancing science not just within the United States, but also reaching students around the world,” said Aharonson. For their next step, the team will look for additional glaciers to conduct more global comparisons, which will further augment our understanding of these debris-covered icy masses.

Further Reading: PSI, Icarus

Martian glaciers are mostly pure ice across the Red Planet, suggesting they might potentially be useful resources for any explorers that might land there one day, a new study finds.

For decades, scientists have often seen glaciers coated in dust on the slopes of the mountains of Mars. Previous research suggested these were either glaciers that were comprised mostly of rock and as little as 30% ice, or debris-covered glaciers that were more than 80% ice.

“Different techniques had been applied by researchers to various sites, and the results could not be easily compared,” study co-author Isaac Smith, a senior scientist at the Planetary Science Institute in Tucson, Arizona and an associate professor of Earth and space science at York University in Toronto, said in a statement.

To shed light on the composition of these glaciers, researchers used the shallow radar instrument (SHARAD) onboard NASA’s Mars Reconnaissance Orbiter to analyze five sites on Mars. They focused on how quickly radar waves moved through a material and how quickly energy dissipated from radar waves into a material, which could shed light on the ratio of rock to ice within the glaciers.

“We found a surprising consistency in the purity of these glaciers,” study co-author Oded Aharonson, a professor of planetary science at the Weizmann Institute of Science in Rehovot, Israel, and a senior scientist at the Planetary Science Institute, told Space.com. “We found all the sites we looked at can be described as relatively pure ice deposits, maybe 80% or more ice, under a rock or dust cover. They could be a resource in the future if humanity tried to access them.”

An example image of a glacier on Mars covered with debris (Image credit: NASA/JPL-Caltech/University of Arizona)

The compositions of these glaciers were similar even in opposite hemispheres. That suggests the environmental conditions in which the ice was formed and preserved were likely consistent across the planet, according to the researchers.

“The ice may have formed through atmospheric precipitation — snowfall that led to glacial formation,” Aharonson said.

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“Or it may have formed through direct condensation — glacial formation directly on the ground via the growth of frost,” he added. “It doesn’t seem like it would have formed through pore ice formation — when water vapor from the atmosphere diffuses to the subsurface and forms ground ice, which we know happens on Mars and terrestrial settings such as Alaska and Antarctica. If the ice in these glaciers had grown that way, we’d expect much higher levels of impurities, and that’s not what we see.”

The researchers next plan to analyze more glaciers on Mars to help solidify their understanding of this ice across the Red Planet.

The scientists detailed their findings online July 12 in the journal Icarus.

Scientists have long been intrigued by the glaciers on Mars, once believed to be primarily composed of rocky rubble with just a small amount of ice. However, new findings are challenging this view, revealing that many of the planet’s glaciers are over 80% pure ice.

80% Pure Ice Found Beneath the Surface

The findings, published in the journal Icarus, came from radar surveys conducted by the Mars Reconnaissance Orbiter. The orbiter’s SHARAD instrument beams radar waves into the Martian surface, allowing researchers to analyze the glaciers’ subsurface composition. For years, scientists had assumed that glaciers on Mars were mostly made up of rocky debris, with a thin coating of ice. However, this new research suggests that the ice content is far higher than previously thought.

The team, led by Yuval Steinberg, a graduate student at Israel’s Weizmann Institute of Science, analyzed radar data from five debris-covered glaciers scattered across both hemispheres of the Red Planet.

The results were surprising. All of the glaciers, whether located near the equator or closer to the poles, displayed nearly identical electrical signatures. This consistency indicates that the glaciers are made up of at least 80% ice by volume, with a thin layer of debris on top, which helps insulate the ice from the planet’s harsh conditions.

Understanding Mars’ icy past

The presence of large glaciers composed mostly of pure ice suggests that Mars has experienced sustained glaciation over millions of years. This means the planet likely underwent multiple ice ages, each of which left behind glaciers composed of snow and frost. The findings provide crucial information about Mars’ climate history, especially the conditions under which these glaciers formed and how they were preserved over time.

Mars today is an arid planet, with little water on its surface and an atmosphere too thin to support liquid water. However, scientists believe that in the past, the planet had enough moisture in the atmosphere to produce significant snowfall. The thick layers of ice beneath the debris are thought to have been buried by dust storms, preserving them for hundreds of millions of years.

A water source for future missions

Beyond its scientific importance, this discovery holds great promise for future missions to Mars. One of the key challenges for astronauts is the need for water, which is essential for drinking, oxygen production, and rocket fuel. Extracting water from ice on Mars is a logical solution, but it is easier said than done if the ice is mixed with rocks or other debris. The new findings suggest that many of Mars’ glaciers are made up of nearly pure ice.

With glaciers located across various terrains, they present promising sites for future human outposts. The study suggests that these ice-rich glaciers could serve as valuable resources for future explorers, providing not only water but also critical insights into Mars’ climate and potential habitability.

The ice, protected by a thin debris layer, could be a vital resource for future human missions, providing easily accessible water, oxygen, and fuel

Mars has long fascinated scientists and space explorers, especially when it comes to the presence of water. Now, new research offers a clearer picture of the glaciers scattered across the Red Planet and it’s exciting news for future human missions. It turns out these glaciers may be made up of more than 80 percent pure water ice, and in some cases, almost entirely of ice.

How do glaciers on Mars look?

On Mars, many of the glaciers lie on mountain slopes and are covered with dust and rocks. For years, scientists believed these formations were mostly rocky with some ice, about 30 percent, or, at best, heavily debris-covered glaciers with more than 80 percent ice. But this new study challenges those earlier views.

What’s new about this study?

Published recently in Science Direct, the research shows a surprising uniformity in the glaciers’ composition. Unlike earlier studies that used different methods on different sites, making it hard to compare results, this one applied a single technique across multiple locations. It found that glaciers in both hemispheres of Mars are made up of a high percentage of clean ice.

One of the researchers, Isaac Smith, explained that earlier research used different tools and focused on different parts of Mars, making comparisons tricky. He is a senior scientist at the Planetary Science Institute and an associate professor at York University in Canada.

What tools did they use?

The team used SHARAD (SHAllow RADar), a radar instrument on NASA’s Mars Reconnaissance Orbiter. By measuring how radar waves travel through the surface and how much of the signal is lost, they were able to estimate the ratio of ice to rock inside the glaciers. Their findings suggest the glaciers have a surprisingly high level of ice purity.

Why is this important?

High-purity glaciers could be a game-changer for human missions to Mars. Water is essential, not just for drinking, but also for making oxygen and rocket fuel. If astronauts can find ice that’s already clean, it will take much less energy to extract and use it, compared to ice that’s mixed with lots of rock and dirt.

According to the study, the clean ice is protected by a thin layer of rock or dust. This layer acts as insulation, keeping the ice safe from Mars’ extreme cold and dry conditions.

How did the ice form?

The researchers suggest a few possible ways the ice might have formed. It could have fallen as snow and collected into glaciers, or it may have formed directly on the ground through condensation. Both processes would lead to fairly clean ice.

What seems unlikely is that the ice formed through what’s called “pore ice”, where water vapour from the atmosphere moves underground and freezes. That process usually leads to more impurities, which weren’t found in these glaciers.

A window into Mars’ past

The consistency of the ice across different glaciers hints that Mars may have gone through a single massive glaciation event, or several smaller ones that had similar conditions.

On the flanks of Martian mountains and crater rims, curious shapes sprawl outward like thick syrup frozen mid-flow. But these are not rivers of rock or lava. They’re massive glaciers, hidden under layers of dust and rubble, and they might just be key to unlocking the planet’s climate history—and to sustaining future human missions.

For decades, scientists believed these Lobate Debris Aprons, or LDAs, were mainly rocky debris lightly laced with ice. The glaciers are found in Mars’s mid-latitudes, between 30 and 50 degrees in both hemispheres, and resemble Earth’s own rock glaciers. But a closer look has flipped that old idea on its head. A new radar survey suggests that these Martian glaciers contain more than 80% pure water ice under just a few meters of dust.

This finding, published in the journal Icarus, suggests Mars has experienced either a single planet-wide glaciation or a series of similar ice ages. And unlike patchy, hard-to-compare studies of the past, this one uses consistent methods across multiple sites, offering a clearer picture of the planet’s frosty past.

This is an example of a debris-covered glacier on Mars. New research into these features suggest that they are purer than once thought, with implications for understanding Mars’ overall water budget and resource utilization on future manned missions. (CREDIT:: NASA/JPL-Caltech/University of Arizona)

Peeling back Mars’s icy layers

The study was led by Yuval Steinberg, a recent graduate of the Weizmann Institute of Science in Israel, alongside senior scientists Oded Aharonson and Isaac Smith from the Planetary Science Institute. Smith is also affiliated with York University in Canada.

They focused on five key glacial sites scattered across Mars, including areas near the equator and in both hemispheres. Each of these had previously been studied using different tools and methods. This made it nearly impossible to compare the results. “Different techniques had been applied by researchers to various sites, and the results could not be easily compared,” Smith explained.

The team aimed to change that by standardizing their approach using data from SHARAD, the Shallow Radar instrument aboard NASA’s Mars Reconnaissance Orbiter. This radar sends radio pulses into the Martian crust and captures how fast and how far they travel. From this, scientists can calculate two important physical properties—dielectric constant and loss tangent. These numbers tell researchers how much ice and how much rock lie beneath the dust.

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Not just dirt-covered rubble

Earlier studies had offered mixed conclusions. Some thought these glaciers were more like rock glaciers, with only about 30% ice. Others suggested they were nearly pure ice, buried under insulating debris. But most of those studies analyzed only a few radar tracks and often used different radar setups or conversion methods.

For this project, the team looked at five sites: three in the northern hemisphere and two in the southern. They examined hundreds of radar tracks, applying a uniform method to all of them. They even added a previously unstudied location near Tempe Terra to expand global coverage.

To their surprise, all five locations showed strikingly similar radar signatures. Each one pointed to a composition of more than 80% water ice, with only a thin top layer of rock and dust.

“This is important because it tells us that the formation and preservation mechanisms are probably the same everywhere,” Smith said. That uniformity means that whatever process formed these glaciers—be it one major glaciation or several similar ones—it affected the whole planet in a consistent way.

The five sites that the team investigated for glacier purity. The fact that these disparate sites contained a similarly high ice-to-rock ratio implies that Mars experienced either one widespread glaciation or multiple glaciations that had similar properties, according to the team. (CREDIT: Steinberg et. al.)

Ice purity points to climate clues

The results also suggest that Mars’s climate once supported widespread snowfall or frost that could build glaciers. Today, the planet is too dry and cold for such activity. So, for glaciers to form and survive, Mars must have had different atmospheric and orbital conditions in the past.

Dielectric constant values between 3.0 and 3.2, and loss tangent values below 0.005, all point to nearly pure water ice. These match those found in Mars’s polar ice caps. By contrast, volcanic flows on Mars give much higher values, proving they are poor in ice.

Knowing how much ice these glaciers contain helps scientists understand how water once moved through Mars’s ancient atmosphere. It also offers insight into how dust storms and orbital tilts may have shaped long-term climate cycles. And with each new radar scan, researchers can refine models of Martian glaciation and better predict where more hidden ice might be buried.

(a) Histogram of all calculated ε’ values in DM. (b) Histogram of all calculated tan δ in DM, using ε’ srf = 5. (CREDIT: Science Direct Icarus)

A global reservoir for future missions

This study does more than shed light on Mars’s past. It also shapes plans for future human exploration.

Water is heavy and costly to haul from Earth. But ice, already on Mars and locked under a thin layer of dust, could supply future crews with drinking water, breathable oxygen, and even rocket fuel.

Pure ice is far easier to use than a mix of stone and frost. You don’t need complex gear to melt or filter it. With vast frozen reserves in many terrains—some even near the equator—Mars becomes more welcoming to long-term missions.

The SHARAD radar’s ability to pinpoint these reservoirs helps planners choose ideal landing and habitation sites. And as more LDAs are studied using the same method, patterns may emerge that reveal local microclimates or even geothermal hotspots that once warmed the crust from below.

Spatial distribution of the calculated tan δ for all detections at PM (using ε’ srf = 5), overplotted on a CTX mosaic. (CREDIT: Science Direct Icarus)

Cracking the Martian cold case

LDAs are part of a broader family of Viscous Flow Features (VFFs), which also include Lineated Valley Fills and Concentric Crater Fills. These formations suggest slow surface flows and glacial activity, just like those seen in cold regions on Earth.

Previous radar studies only covered a few sites. For example, Holt et al. (2008) looked at Hellas’s eastern rim and found near-pure ice. Gallagher et al. (2021) studied Phlegra Montes and found similarly promising values. Petersen et al. (2018) performed one of the most thorough studies, analyzing over 500 tracks in Deuteronilus Mensae, showing consistent ice purity.

Steinberg’s new work expands that foundation, unifying the data and bringing clarity to an area previously marked by confusion and conflicting methods.

Radargram cropped to the LDA area, highlighting the marked interfaces. (CREDIT: Science Direct Icarus)

It’s not just about counting how much ice is there. It’s about understanding the story the ice tells—the cycles of snow and dust, the shifting tilt of Mars’s axis, and the way time sculpted a once-wetter world into the dry desert we see today.

As Aharonson pointed out, “This study highlights how NASA programs are advancing science not just within the United States, but also reaching students around the world.”

And Mars, it seems, still has many frozen secrets to tell.

Note: The article above provided above by The Brighter Side of News.