“What the heck?!” glaciers on Mars

Overview map

Another
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Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on June 29, 2025 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It falls into what I call my “What the heck?!” category of Martian land-forms, simply because their shape is so strange and inexplicable it is difficult to conceive a geological process that could create them.

Nor does it help much that we know what these land-forms are made of. The white dot on the overview map above marks the location, inside the 2,000-mile-wide northern mid-latitude strip I label glacier country, because almost every image taken shows glacial features. In this case, this strange geology is located on the floor of a canyon that is part of a large region of chaos terrain, a landscape typical of glacier country. This floor, as well as all the low areas, seems filled with glacial flows. This particular canyon appears to roughly flow downhill to the northwest, though the downhill grade in the entire region varies widely in all directions.

Based on all the orbital data, these flows are glacial in nature, the ice protected by a thin top layer of dirt and debris. The strange features at the top of all the small mesas in the picture above suggest that the wind possibly blew off the dirt and debris, exposing the ice and allowing it to sublimate away. This in turn produced the knobby hollows at the top of each mesa.

I am guessing, and no one should trust my guess considering I only make believe I’m a geologist on the internet.

Perseverance looks west

Perseverance looks west
Click for full resolution. For original images go here and here.

Overview map
Click for interactive map.

Cool image time! The panorama above, reduced and sharpened to post here, was created using two pictures taken on August 28, 2025 by the left navigation camera on the Mars rover Perseverance (here and here).

The blue dot on the overview map to the right marks Perseverance’s location when it took these pictures. The yellow lines indicate the approximate area covered by the panorama. The red dotted line indicates the rover’s planned route, with the white dotted line its actual travels.

The recent geological research focused on the lighter-colored ridge on the right center, dubbed Soroya. From the August 27, 2025 update by the science team:

Soroya was first picked out from orbital images as a target of interest because, as can be seen in the above image, it appears as a much lighter color compared to the surroundings. In previous landscape images from the surface, Mars 2020 scientists have been able to pick out the light-toned Soryoa outcrop, and they noted it forms a ridge-like structure, protruding above the surface. Soroya was easily identifiable from rover images as Perseverance approached since it indeed rises above the surrounding low-lying terrain.

The view is looking downhill away from Jezero Crater. The curve of the horizon is an artifact of the navigation camera’s wide view, accentuated by the slope that the rover sits on. The low resolution of this western region on the overview map is because the science team has not yet had Mars Reconnaissance Orbiter (MRO) get highest resolution pictures there yet.

Note the utter barrenness of this terrain. This is Mars, a lifeless world that has only the future potential for life, once we humans start to colonize it. Whether there was ever any past life remains uncertain, but the nature of its terrain as seen by both Perseverance and Curiosity suggests strongly that past life never existed, or if it did it barely survived and was quickly wiped out, a long time ago.

Another great hiking location on Mars

Another great hiking location on Mars
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In honor of our just completed visit to the south rim of the Grand Canyon, today’s cool image takes us to another location on Mars that to me appears a perfect place to install some hiking trails. The picture to the right, cropped, reduced, and sharpened to post here, was taken on June 30, 2025 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

The image shows a two-mile wide canyon with a number of scattered narrow mesas within. The north and south rims rise about 550 feet above the canyon floor. The two mesas labeled “A” and “B” rise about 200 and 100 feet respectively.

The hiker in me immediately imagines what a great hike it would be to go up the western nose of either ridge and walk along its crest. The knife-edge nature of ridge “A” would mean that for a large majority of the hike you’d be at the north and south edges at the same time.
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Sand dunes inside the Martian north polar icecap

Sand dunes inside the Martian north polar icecap
Click for original image.

Today’s cool image returns to the Martian north pole. The picture to the right, rotated, cropped, reduced, and enhanced to post here, was taken on July 3, 2025 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows the top of a ridge near the edge of that icecap, with dunes visible in the hollow several thousand feet below.

The angle of this picture does not show us the many layers on the cliff leading down to those dunes. It does show evidence, however, of the top few layers on the flat crest of that ridge. The white lines delineate those layers, each line marking the edge of a series of wide terraces.

The dunes in the canyon below are of interest because their source is likely the dust that is mixed into thick icecap’s ice. As that ice sublimates away on the face of the cliff, the dust falls into the canyon, where it is trapped.
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The beauty of Mars’ many-layered northern icecap

The beauty of Mars' ice cap
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Cool image time! The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on July 1, 2025 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

The science team labels it clumsily as “North Polar layered deposits structural geology in icy layers”. What we see are the many layers that make up the north polar cap, produced by the red planet’s many climate cycles that scientists think Mars has undergone over the eons as the red planet’s rotational tilt, or obliquity, rocked back and forth from 11 degrees inclination to as much as 60 degrees. At the extremes, the ice cap was either growing or shrinking, while today (at 25 degrees inclination) it appears to be in a steady state.

These layers are a mixture of ice and dust. The variations from dark to light likely indicate changes in the amount of dust in the atmosphere. Dark layers suggest the atmosphere was more dusty due to volcanic eruptions. Light layers suggest the planet’s volcanic activity was more subdued.

At least that’s one hypothesis.
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Wind-eroded terrain on the edge of Mars’ largest volcanic ash field

Wind-eroded terrain in Mars' largest volcanic ash field

Cool image time! The picture to the right, cropped and sharpened to post here, was taken on July 2, 2025 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

Labeled simply as “wavy terrain” by the MRO science team, it shows a relatively flat plain of hollows and terraced ridges that suggest the prevailing winds come from the west-southwest. As they blow, they slowly cause the layers of material to peel away, exposing those terraces.

This wavy landscape extends for many miles to the west, covering a region 135 by 160 miles in area. The layering and wavy nature of the terrain suggests the material here is fragile and easily peeled away by the winds of Mars’ very thin atmosphere. Think of the sandstone that forms Monument Valley and Canyonlands in the southwest United States, shaped almost entirely by wind.

And in fact, the overview map below confirms this.
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Slumping landslide in Mars’ glacier country

Overview map

Slumping landslide in Mars' glacier country
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Cool image time! The picture to the right, rotated, cropped, reduced, and sharpened to post here, was downloaded on July 1, 2025 from the high resolution camera on Mars Reconnaissance Orbiter (MRO).

Labeled by the science team as a “flow,” it shows what appears to be a major collapse of the canyon’s south wall. The white dot on the overview map above marks the location, near the center of the 2,000-mile-long strip in the northern mid-latitudes of Mars that I label “glacier country” because almost every single high resolution image of this region shows glacial features.

This picture is no exception. First, the canyon appears filled with a glacial material, though its flow direction is unclear. Orbital elevation data suggests that this collapse is actually at the canyon’s high point, with the drainage going downhill to the east and west.

Second, the collapse itself doesn’t look like an avalanche of rocks and bedrock, but resembles more a mudslide. Since liquid water cannot exist in Mars’ thin atmosphere and cold climate, the soft nature of the slide suggests it is dirt and dust impregnated with ice. At some point, either because of the impacts that created the craters on its southern edge or because the sun warmed the ice causing it sublimate away thus weakening the ground structurally, the entire cliff wall slumped downward to the north.

The canyon itself is about 800 feet deep. It likely formed initially along a fault line, with ice acting over time to widen and extend it.

Gullies on a crater wall in the icy north of Mars

Gullies on a crater wall
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Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on July 4, 2025 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows the lower right quadrant of a five-mile-wide unnamed crater in the high northern mid-latitudes of Mars.

The science team in its label for this picture focuses on the gullies visible on the crater’s interior wall. To my Earth-bound eye, these gullies look like recent erosion caused by underground ice sublimating into gas, causing the surface to collapse downward into the crater. This however is a purely uneducated guess.

The floor of the crater however shows features that resemble glacial fill, seen in numerous high latitude craters on Mars. This is not surprising, as the crater is located at 59 degrees north latitude, close enough to the pole for there to be a lot of near surface ice to be present.
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Slope streaks within Mars’ largest mountain region

Overview map

Today’s cool image revisits Lycus Sulci, the largest mountain range on Mars, about 1,400 mile wide and 1,800 miles long. The overview map to the right gives a sense of the roughness and chaotic nature of this region, extending north from Mars’ largest volcano, Olympus Mons.

At present scientists are unsure of the geology that formed Lycus Sulci, and how it is linked with Olympus Mons. The wide view to the right suggests it is the remains of a very ancient lava flow descending from the volcano that over time has become eroded to produce this wildly knobby terrain. That hypothesis remains unproven however. There is also evidence that the material here might instead be volcanic ash, deposited in many layers and eroded away with time.

The location of the cool image below is marked by the white dot, with the inset providing us a wider view of the surrounding terrain. Note the two craters to the north and west. Both appear to have been partly filled by flows coming from the south and east, respectively, adding weight to the theory that this region formed from lava flow.
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When Martian lava meets a Martian mountain

When Martian lava meets a Martian mountain
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Cool image time! The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on April 24, 2025 by the high resolution camera on Mars Reconnaissance Orbiter (MRO), and was posted yesterday by the science team to illustrate the vast lava flows that cover much of Mars. From the caption:

This image captures the edge of a lava flow that partially buries older terrain in the Martian Southern Highlands. Where the edge of the lava flow made contact with the higher-standing topography, it formed a rumpled and ridged surface.

This lava flow is one of many massive flows that extend southwest from Arsia Mons, one of the largest shield volcanoes on Mars.

The mountain to the south rises about 3,700 feet above that rumpled lava ocean at its base.
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Strange rocks on Mars

Coral on Mount Sharp!
Click for original image.

Float rock in Jezero Crater
Click for original image.

Time for two cool images, from two different craters separated by thousands of miles on Mars! The first image to the right, cropped, reduced, and sharpened to post here, was taken on July 24, 2025 by the Mars Hand Lens Imager (MAHLI) at the end of the robot arm of Mars rover Curiosity, and shows a really strange rock formation that resembles a piece of coral on Earth.

Curiosity has found many small features like this one, which formed billions of years ago when liquid water still existed on Mars [in this region]. Water carried dissolved minerals into rock cracks and later dried, leaving the hardened minerals behind. Eons of sandblasting by the wind wore away the surrounding rock, producing unique shapes.

The second image, cropped, reduced, and sharpened to post here, was taken on August 5, 2025 by the left high resolution camera on the rover Perseverance. It shows what appears what geologists call a “float rock”, something that was created geologically somewhere else and transported to this location later.

In this case the rock appears lavalike in nature. Since Perseverance is exploring the exterior rim of Jezero Crater, we could be looking at the impact melt created when the bolide hit the ground to create the crater. Material would be instantly melted as well as flung outward as ejecta, with this strangely shaped rock an example.

The problem with this theory however is that the rock appears to have solidified well before it hit the ground at this location. Its shape also suggests it solidified within a crack, thus molding it to this shape, with its top once at the bottom, the lava flowing downward. The mystery then is how it ended up as we see it, upside down and exposed.

Curiosity looks back

Curiosity looks back
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Cool image time! The picture to the right, reduced and enhanced to post here, was taken on July 28, 2025 by the left navigation camera on the Mars rover Curiosity. It looks to the north, down the flanks of Mount Sharp and across the floor of Gale Crater to its mountainous rim about 30 miles way, seen on the horizon.

The view is so clear because of the season, as noted in the science team’s blog post today:

We’re still in the time of year where the atmosphere at Gale is reasonably dust-free (at least, compared to later in the year), allowing us to look all the way out to and beyond the Gale crater rim. The upper slopes of Mount Sharp have also re-emerged to our east after spending months hidden behind the walls of Gediz Vallis. There’s a bit more sand and dust in this location than we’ve seen recently, so we can also see the trail left behind by the rover’s wheels as we drove to this location

The ridge in the foreground is an example of the boxwork Curiosity is presently traversing. It is now on one of those ridges, and will be moving along it in short drives as the science team studies the geology here. The rover’s tracks leading up to this position can be seen clearly.
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Mars and its two moons seen in the infrared by Europa Clipper

Mars and its two moons
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Cool image time! The infrared image to the right, cropped, reduced, and enhanced to post here, was taken by Europa Clipper on February 28, 2025 just before it flew past Mars on its way to Jupiter.

Deimos is in the upper left corner, while Phobos is close to Mars.

When the image was taken by the mission’s Europa Thermal Emission Imaging System (E-THEMIS), the spacecraft was about 560,000 miles (900,000 kilometers) from the Red Planet. The image is composed of 200 individual frames, part of a continuous scan of 1,100 frames taken roughly a second apart over a period of 20 minutes. Scientists are using the tiny, point-like images of the moons to check the camera’s focus.

As this is an infrared image (measuring heat), it shows Mars’ northern polar cap as the dark oval at the top of the planet. The bright (and thus warmer) oval to the lower left is the shield volcano Elysium Mons.

This data suggests Europa Clipper’s thermal instrument is working as intended, which is essential for observing the ice content (if any) on Europa once it enters Jupiter orbit in 2030.

The glaciers on Mars are almost pure ice with only a thin cover of dust and debris

A map of glaciers on Mars
A map of glaciers on Mars.

According to new research, scientists now think that the glaciers on Mars are almost pure ice, protected from sublimation by a thin cover of dust and debris.

Work over the last 20 years has demonstrated that at least some of these glaciers are mostly pure ice with only a thin cover of rock and dust, but according to a new paper published in Icarus, glaciers all over the planet actually contain more than 80% water ice, a significant finding. Ultimately, this means that Mars’s glacial ice deposits are nearly pure across the globe, providing a clearer understanding of Mars’ climate history and a possible resource for future utilization.

The researchers analyzed mid-latitude glaciers at five different locations in both the north and south hemispheres, and found that at every location the data suggested almost pure ice.

The map to the right, from earlier research, shows the prevalence of near-surface ice once you get above 30 degrees latitude. From the poles to the mid-latitudes it appears there is an ice sheet or “ice table” just below the surface. In the mid-latitudes glaciers dominate, as this appears to be the region where that ice is beginning to dissipate. In the equatorial regions little or no near-surface ice has been detected, though there has been some evidence in some places of ice at deeper depths.

This data once again demonstrates that Mars is not a desert like the Sahara, as we once believed. Instead, it more resembles Antarctica, where there is ice everywhere that simply needs to be processed for use.

Curiosity amid the boxwork

Curiosity amid the boxwork, looking uphill
Click for original image.

Overview map
Click for interactive map.

Cool image time! The panorama above, cropped to post here, was taken on July 20, 2025 by the left navigation camera on the Mars rover Curiosity. It looks uphill to the south into the canyon that Curiosity will eventually travel, with the white chaotic upper flanks of Mount Sharp on the horizon. The mountain’s peak itself is out of view, about 25 miles away.

The overview map to the right provides the context. The blue dot marks Curiosity’s present position, on the northern edge of the large patch of very distinct boxwork ridges visible from orbit. You can see these ridges in the foreground of the panorama above.

The yellow lines indicate the approximate area covered by the panorama. The red dotted line roughly indicates the rover’s future travels. At the moment, however, it is going nowhere, as the science team is focused on studying these boxwork ridges in the hope they can determine their origin. Such features are usually associated with cracking later filled with lava, with the polygon-shaped cracking usually associated with a formerly wet environment drying.

Weird drainages on Mars

Weird drainages on Mars
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Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on Februay 11, 2025 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). The camera team posted it yesterday as their own cool image, labeling it “A Fissure and Channel near Pavonis Mons”. From the caption:

A linear trough strikes northeast, then abruptly ends (or changes into a narrow ridge). Where the trough ends, a sinuous channel has an east-southeast strike, trending at almost a right angle to the trough. What happened to form these features?

We can speculate that first there was a southwest-to-northeast trending fracture or fault, perhaps associated with a volcanic vent. Groundwater (or some other runny fluid) coursed through the fault until overflowing and forming the sinuous channel. Continued movement through the fault carved a trough up to the overflow point.

The arrows indicate the downhill grades. Though this caption mentions groundwater, it is far more likely that the “runny fluid” was lava, as shown by the overview map below.
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New census of inverted channels on Mars strongly suggests the planet once had more water

Martian ridges that imitate rivers
Click for original image.

A new review of inverted channels on Mars now strongly suggests that the red planet was once far wetter than presently seen, with the channels implying the existence of liquid rivers.

The discovery of more than 15,000 kilometres of ancient riverbeds on Mars suggests that the Red Planet may once have been much wetter than previously thought. Researchers looked at fluvial sinuous ridges, also known as inverted channels, across Noachis Terra – a region in Mars’ southern highlands. These are believed to have formed when sediment deposited by rivers hardened and was later exposed as the surrounding material eroded.

Similar ridges have been found across a range of terrains on Mars. Their presence suggests that flowing water was once widespread in this region of Mars, with precipitation being the most likely source of this water.

The image to the right is a good example of an inverted channel, a previous cool image posted in April 2025. It is located not in Noachis Terra but in the northern lowland plains.

The researchers argue that these channels suggest that about 3.7 billion years ago there were flowing liquid rivers on Mars, fed by precipitation. This conclusion however still does not explain how this could happen on a planet that is too cold with too thin an atmosphere for liquid water to exist. Every model so far proposed to make Mars warmer with a thicker atmosphere in the distant past remains questionable with many holes.

Could the inverted channels have been created by glacial activity, ice instead of liquid water? At present we don’t know enough about the Mars environment and the physics of such things in the planet’s one-third gravity to answer that question. It is however a question that scientists I think should be asking, based on the extensive evidence of glacial activity in the Martian mid-latitudes.

The big takeaway from this study however is that it adds weight to the overall trend seen in the data, that over time the total amount of water on the planet has declined. We can see this in glaciers, for example, with later glacial flows always falling short of previous flows. This research shows that even in the dry tropics there was once ample water, even if we don’t yet know what form it took.

Sightseeing near Starship’s candidate Martian landing sites

An interesting mesa near Starship's Martian landing zone
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Today’s cool image takes us sightseeing in the region on Mars that SpaceX has chosen for its prime landing zone for its Starship spaceship. The picture to the right, cropped, reduced, and sharpened to post here, was taken on May 29, 2025 by the high resolution camera on Mars Reconnaissance Orbiter (MRO), and shows a 465-foot-high unusually shaped mesa in this region.

The full resolution inset at the bottom of the picture focuses at the strange tilted layers on the southern slope of this mesa. Apparently the layers at this spot were pushed sideways so they lie significantly angled to the horizontal. Though it isn’t clear from this picture, it is possible that the mesa itself is made up of similar tilted layers, hidden below the surface. We can see the tilt only on the mesa’s southern flank because erosion has apparently exposed it.

Note also the black stain that surrounds the mesa. Though this might be caused by wind distributing dust, such stains have also been seen at a location where scientists suspect an inactive hot spring might exist, as well as another location where there may have been relatively recent volcanic activity.

Is this stain caused by any of these processes? In situ exploration would probably be necessary to find out. And we may soon actually have spaceships landing here in the relatively near future with the capability to do this.
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Returning to Mars’ glacier country

Overview map

Returning to Mars' glacier country
Click for original image.

Today’s cool image illustrates again why I rail against those who still claim Mars is dry. The picture to the right, cropped, reduced, and sharpened to post here, was taken on June 2, 2025 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

The picture was labeled simply as a “terrain sample” by the MRO camera team, which almost always signifies that it was taken not as part of any specific science research project or by request by a scientist, but to fill a gap in the camera’s schedule in order to maintain its proper temperature. When such a gap-filler picture is required, the team tries to pick interesting features in that time frame, but don’t always succeed.

In this case, that time frame placed MRO over the northern mid-latitudes and a region I label “glacier country” because practically every picture taken in this region shows glacial features. This picture is no exception. The white dot in the overview map above marks the location, in the Protonilus Mensae area of the 2,000-mile-long strip of glaciers. The arrow in the picture itself shows the downward grade of the glacial flow. The small 2,000-foot-wide crater appears as if the impact occurred on soft ice, and the stippled terrain surrounding it appears to resemble the feature geologists have labeled “brain terrain”, a surface feature unique to Mars and associated with near surface ice, though its exact formation process is not yet understood.

Nor have I cherry-picked this image to prove my point. Its glacial-like features are very typical for this region of Mars. Note for example the inset with the larger crater to the northeast. It appears almost buried by this glacial material, which has poured through the gap in its southwest quadrant to fill it. A close look at all the low lying terrain shows similar glacial-like flows.

Mars is surely not a paradise. It is bone-chillingly cold almost all the time. Its atmosphere is so thin and lacking in oxygen you would quickly suffocate if you tried to breath it. But the data continues to suggest that the red planet has ample supplies of near-surface ice outside of its dry tropics. All future colonists will need to do is dig a bit and process the water out.

Mars is not dry!

Global map of glaciers found on Mars

I once again feel compelled to rant against the shallow ignorance of too many people in both the journalism field as well as academia about the most recent data we now have of Mars. Two articles today once again show this ignorance, assuming blandly that Mars is a dry planet with little water on it anywhere, when orbital data over the past decade has unequivocally shown that — except for its equatorial regions — the planet is covered with a LOT of near-surface ice.

The headlines make this ignorance quite clear:

In both cases, the articles assume that the data obtained from rovers and landers in the dry Martian tropics applies to the entire planet. It does not. This evidence of a dry planet carries a bias that comes from the decision by the planetary community as well as NASA to send every rover to that dry equatorial region. Only one lander, Phoenix, has ever been successfully dropped far from the Martian equator, and it was purposely sent to a very high latitude, where it proved there was ice present just below the surface.

Orbital data in the past decade from both Mars Reconnaissance Orbiter and Mars Express has clearly shown that there is a lot of near surface ice on Mars, as shown by the map above. In the mid-latitudes the terrain is dominated by glaciers, as this is the region where the vast ice sheets in the high latitudes begin to fade away.

Only the equatorial region, indicated by the white lines on the map, is dry and barren. And yet, even here, orbital data has detected evidence that suggests underground ice still exists.

It seems to me that journalists and academic PR departments should know these facts, and include them in any reports about the dry nature of Mars’ equatorial regions.

The sagging flank of one of Mars’ giant volcanoes

The sagging flank of Elysium Mons
Click for original image.

Cool image time! The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on May 1, 2025 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows what the science team labels a “chain of pit craters in [a] graben”.

A graben is a surface fissure created when the surface either spreads or two sections shift sideways in opposite directions. The chain of pits suggest that there is a larger void below into which the surface is sinking. It is also likely that a lot of the sinking material is volcanic ash, thrown free in an eruption hundreds of millions of years ago, which over the eons has been blown up to this location to settle in the crack to fill it. It is now trapped there, and sinking.

What caused the ground here to shift and create the fissure? In this case, the cause is quite large and massive, in a way that boggles the mind.
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The source of a Martian glacial canyon 750 miles long

The source of a Martian glacial canyon 750-miles-long
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Cool image time! The picture to the right, cropped, reduced, sharpened, and brightened to post here, was taken on May 1, 2025 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

The scientists label this very simply as a “wall on Ausonia Cavis”. Ausonia Cavis — 31 miles long and 20 miles wide at its widest — is one of the many gigantic sinks found in many places on Mars. This particular cliff wall is about 2,000 feet high, though from rim to floor of the sink is closer to 3,000 feet.

The image was likely taken to get a closer look at those gullies flowing down the cliff wall. Previous research of similar cliff walls in this region has found what appears to be seasonal water frost in such gullies, and this image was likely taken to see if more such frost could be spotted here as well.
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Sublimating ice in the Martian dry tropics?

Sublimated ice in the Martian dry tropics?
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Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on May 3, 2025 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). Labeled merely as a “terrain sample,” it was likely snapped not as part of any specific research project but to fill a gap in the camera’s schedule so as to maintain the camera’s proper temperature.

When the MRO camera team does this, they try to pick features of interest at the time required, and I think succeed more often than not. In this case, they captured this one-mile-wide unnamed crater that appears to be filled with sublimating glacial debris. Similarly, the plateau surrounding the crater seems to also show signs that some sublimation is occurring of ice just below the surface, producing the areas that appear filled with pockmarks.

The location however suggests that if near surface ice here is sublimating away, it hints at a find of some significance.
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Mars will be mystery until we can walk its surface

A Martian mystery
Click for original image.

Today’s cool image illustrates starkly the limitations of orbital imagery. The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on March 30, 2025 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows flow features inside a depression that strongly resemble glacial features, with the downhill grade roughly heading south.

Such features are seen in many places on Mars, almost always in the 30 to 60 degree mid-latitude bands in both the northern and southern hemispheres (see here, here, and here for just three examples. For many more simply search this website using “glacier” or “glacial feature” as search terms).

The problem is that this location is not within that 30 to 60 degree latitude band. In fact, at this location no near surface ice should exist at all.
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The mad mountains of Mars

The mad mountains of Mars
Click for original image.

Overview map
Click for interactive map

Cool image time! The picture above, cropped to post here, was taken on June 10, 2025 by the high resolution camera on the Mars rover Curiosity, and shows some of the stranger terrain found higher up the flanks of Mount Sharp in Gale Crater.

The blue dot on the overview map to the right marks Curiosity’s present position, where it is doing another drilling campaign into the first boxwork geology it has encountered. The white line marks its past travels, while the green dotted line its planned route.

The yellow lines indicate the area seen in the picture above. The wild mountain peaks on the horizon are part of the sulfate-bearing unit that appears very bright in the overview map. The material that makes up this terrain appears to be very easily eroded, based on its features as seen from orbit, as well as Curiosity’s distant view. Whether that erosion was wind, water, or ice, remains undetermined, and is the main question Curiosity will attempt to answer once it gets there, likely in a year or so.

Regardless, the landscape appears almost like it soft sand being washed away.

Where the rover will go next the science team has not yet decided. It will definitely continue uphill, but they do not yet know the route they will take through that sulfate-bearing unit.

The dusky mountains of Mars

The dusky mountains of Mars
Click for high resolution. For the original images, go here, here, and here.

Overview map
Click for interactive map.

Cool image time! The panorama above, created from three images taken on June 7, 2025 (here, here, and here) by the high resolution camera on top of the Mars rover Curiosity, looks south and uphill into the Gediz Vallis canyon that the rover had been traveling previously.

The overview map to the right provides context. The blue dot Curiosity’s present position, where it is about to begin a drilling campaign into the first boxwork structures the rover has reached. The white dotted line marks its past travels, while the green dotted line its planned future route. The red dotted line marks a planned route that has been abandoned.

The yellow lines indicate approximately the area covered by the panorama. Because this used the rover’s high resolution camera, the view gives us a detailed look at the mountains on the distant horizon. Though we are looking uphill, the peaks in the distance are merely higher ridges and hills on the flanks of Mount Sharp. The mountain’s peak is out of view, about 25 miles away and about 15,000 feet higher up.

Note the dusty and what appears to be a softened nature of the terrain on these higher peaks. Since entering the foothills of Mount Sharp several years ago, the surface has been extremely rocky and rough, every inch covered in boulders of all sizes. This distant view suggests the ground might become easier to traverse at those higher altitudes. It also appears there will be a lot more dust, coating everything.

The lighting I think is close to natural. Because Mars is farther from the Sun, it doesn’t get as much light. Even during mid-day the light to our Earth-borne eyes would more resemble dusk on Earth.

Scientists believe they have detected the actual process in which Mars loses its atmosphere

The uncertainty of science: Scientists using three different instruments on the Mars orbiter MAVEN now believe they have detected evidence of the actual process in which Mars loses its atmosphere, dubbed “sputtering”.

To observe sputtering, the team needed simultaneous measurements in the right place at the right time from three instruments aboard the MAVEN spacecraft: the Solar Wind Ion Analyzer, the Magnetometer, and the Neutral Gas and Ion Mass Spectrometer. Additionally, the team needed measurements across the dayside and the nightside of the planet at low altitudes, which takes years to observe.

The combination of data from these instruments allowed scientists to make a new kind of map of sputtered argon in relation to the solar wind. This map revealed the presence of argon at high altitudes in the exact locations that the energetic particles crashed into the atmosphere and splashed out argon, showing sputtering in real time. The researchers also found that this process is happening at a rate four times higher than previously predicted and that this rate increases during solar storms.

This sputtering is believed to be the process in which Mars lost the thick atmosphere that scientists believe must have existed in the past so that liquid water could exist on the planet’s surface. When MAVEN arrived in Mars orbit ten years ago the scientists actually thought the spacecraft would detect it relatively quickly. That it took ten years to finally find some evidence it is occurring suggests something is not quite right with their theories.

New data suggests Europa’s surface is constantly changing

Webb data showing variations on Europa's surface
Click for original graphic.

The uncertainty of science: Using data collected by the Webb Space Telescope combined with modeling and lab experiments, scientists now think they have found evidence that Europa’s surface is constantly changing, with materials from its interior being brought to the surface.

This new study found crystalline ice on the surface as well as at depth in some areas on Europa, especially an area known as Tara Regio. “We think that the surface is fairly porous and warm enough in some areas to allow the ice to recrystallize rapidly,” said Dr. Richard Cartwright, lead author of the paper and a spectroscopist at Johns Hopkins University’s Applied Physics Laboratory. “Also, in this same region, generally referred to as a chaos region, we see a lot of other unusual things, including the best evidence for sodium chloride, like table salt, probably originating from its interior ocean. We also see some of the strongest evidence for CO2 and hydrogen peroxide on Europa.”

…“Our data showed strong indications that what we are seeing must be sourced from the interior, perhaps from a subsurface ocean nearly 20 miles (30 kilometers) beneath Europa’s thick icy shell,” said [Dr. Ujjwal Raut of the Southwest Research Institute and co-author of the paper]. “This region of fractured surface materials could point to geologic processes pushing subsurface materials up from below. When we see evidence of CO2 at the surface, we think it must have come from an ocean below the surface.”

The graphic to the right shows the detected variations across the surface of Europa, based on the Webb spectroscopic data. It also illustrates nicely the coarseness of this data, its lack of resolution, and the uncertainties involved. The scientists have found evidence that suggests the surface is changing, but the key word here is “suggests”. They have not yet directly seen any actual changes, such as changes between two images taken at different times.

Nonetheless, the data does point in the right direction. Moreover, it would be far more unlikely if nothing on Europa changed. The fundamental question that remains unanswered is how fast things change there. And we won’t have any chance to answer this question until Europa Clipper enters Jupiter orbit in 2030 and begins multiply fly-bys of Europa.

The canyon that Curiosity will eventually climb

The canyon that Curiosity will eventually climb
Click for full resolution. For original images go here and here.

Overview map
Click for interactive map.

Cool image time! The panorama above, created from two photographs taken on May 23, 2025 by the left navigation camera (here and here) on the Mars rover Curiosity, looks south uphill into the canyon that Curiosity is eventually going to climb.

The overview map to the right provides the context. The blue dot marks Curiosity’s present position, the white dotted line its past travels, the red dotted line its initial planned route, and the green dotted line its future route. The yellow lines indicate the approximate area seen in the panorama above.

If you look on the horizon to the left, you can see very bright terrain higher up the mountain. This is the pure sulfate-bearing unit that is Curiosity’s next major geological goal. It won’t reach that terrain for quite some time however because first the scientists want to spend some time studying the boxwork geology that Curiosity is now approaching. That boxwork suggests two past geological processes, as yet unconfirmed. First it suggests the ground dried like mud, forming a polygon pattern of cracks that then hardened into rock. Second, lava seeped up from below and filled those cracks. The lava, being more resistant to erosion, ended up becoming the boxwork of ridges as the material around eroded away.

This proposed history however is not proven. They hope to find out when Curiosity gets there.

Meanwhile, despite having traveled almost 22 miles, the rover is more than 25 miles from the peak of Mount Sharp, which remains out of sight. That peak is also about 15,000 feet higher.

Scientists: Jezero Crater’s theorized lake overflowed intermittently four times in the past

The inlet and outlet valleys of Jezero Crater
Click for original image.

Scientists analyzing the Martian geology of the meandering outflow canyon from Jezero Crater, now think it was formed by four different very short-lived events when the theorized lake inside the crater overflowed the crater rim.

The map to the right, figure 1 of the paper (cropped and annotated to post here), provides the context. Two canyons, Sava Vallis and Neretva Vallis feed into Jezero Crater, and one canyon, Pliva Vallis, flows out. From the abstract:

By examining the shape of the valley, we noticed that Pliva Vallis was not like valleys carved by continuous rivers on Earth and propose instead that the valley was carved by at least four episodes of lake overflow. To give a minimum estimate of the duration of these events, we use a numerical model to simulate the overflow of a lake and the incision of a valley. Modeling suggests that the four (or more) episodes identified each incised part of the valley and that each episode lasted a few weeks at maximum.

The researchers also considered whether Pliva Vallis could have been carved by glacial flows, but rejected that possibility partly because “the general morphology of the valley shows a decrease in depth and width downstream, while subglacial channels [on Earth] tend to remain of similar width or become larger, as the flow regime does not decrease downstream.”

These conclusions of course carry a great deal of uncertainty. For one, they are based solely on orbital data. No ground truth exists as yet. Secondly, they assume the geology on Mars behaves in the same manner as on Earth. It could very well be for example that the reason the valley shrinks in size is because its Martian glacier sublimated away as flowed downhill, something that doesn’t happen on Earth.

Regardless, the data strongly suggests that water shaped Jezero in some manner.

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