Cracks in Martian lava

Cracks in Martian lava
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Cool image time! The picture to the right, rotated, cropped, and reduced to post here, was taken on January 25, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It was taken not as part of any specific research project, but to fill a gap in MRO’s picture-taking schedule in order to maintain the camera’s temperature. When such pictures need to be taken, the camera team tries to find something of interest in the area to be shot. Sometimes the picture is boring. Sometimes fascinating. Today’s picture I think falls into the latter category.

This is a lava flood plain, as shown in the overview map below. The meandering ridges are likely what geologists call lava dikes, places where lava was extruded out through a fissure. This suggests that the flat flood lava was an older crust, and that there was hot molten lava below it that eventually pushed its way up through cracks in that crust.

This hypothesis however is not certain, as the meandering nature of the ridges does not correspond well with what one would expect from such crustal cracks.
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Flat-topped mesas in the icy northern lowland plains of Mars

Flat-topped Martian craters
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Cool image time! The picture to the right, cropped and rotated to post here, was taken on December 27, 2022 by the high resolution camera on Mars Reconnaissance Orbiter (MRO), and shows what the scientists have labeled “flat topped hills in Utopia Planitia.”

Utopia Planitia is the largest impact basin on Mars, approximately 2,100 miles across and located in the northern lowland plains.

Orbital evidence strongly suggests it is a region with a lot of near surface ice. The picture to the right reinforces that conclusion, as the entire flat plain surrounding these buttes appears like an ice field. Moreover, the full image shows many craters filled with glacial features, most of which also have softened features, as if with time the ice that impregnates their material has sublimated away.
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An inactive volcanic vent on Mars

An inactive volcanic vent on Mars
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Cool image time! The picture to the right, rotated, cropped, and reduced to post here, was taken on October 5, 2022 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). Labeled by the science team as “Vents and Lava Flows on Flank of Pavonis Mons,” the section to the right shows the picture’s largest vent. The downhill grade is to the south.

In the full photo you can see that this vent sits on top of a flat mound of hardened lava, all of which flowed from the vent in the distant past. The main flow of course went to the south, out the channel and down the flanks of Pavonis Mons, the middle volcano in the line of three just to the west of Mars’ giant Valles Marineris canyon. The caldera peak of Pavonis Mons is about 35 miles away, and sits at a height of 47,000 feet elevation, far higher than Mount Everest but still only the fourth highest Martian volcano.

In the full picture, the entire surface also generally flows south, except for a crack that goes from northeast to southwest, possibly caused when the mountain flank sagged to the south.
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Sightseeing in the region near the Starship Mars landing zone

Sightseeing in the region near Starship's landing zone
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Cool image time! The picture to the right, cropped and reduced to post here, was taken on November 30, 2022 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows a bulbous hill in the icy northern lowland plains of Mars. That it is icy here is indicated by the glacier features that appear to fill the small crater near the bottom of the picture.

You can get a better sense of stark alien nature of this terrain by looking at an MRO context camera image of the same area, taken on April 1, 2008. The subject hill is the first hill on the image’s west side, going from the top. This is a flat plain interspersed with crater splats, mounds of a variety of sizes, and a puzzling meandering dark line that suggests a crack from which material is oozing.

The geology to be studied here might be endless but for tourists the views will be astounding in their alienness.
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A Martian glacier waterfall?

A Martian glacier waterfall?
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Cool image time! The photo to the right, cropped, reduced, and sharpened to post here, was taken on October 25, 2022 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows a small meandering canyon that appears to drain into a larger side canyon, all part of a region of chaos terrain dubbed Galaxias Chaos in the Martian northern mid-latitudes.

Though the latitude is 35 degrees north, where we should see lots of evidence of glacial features, especially because this is chaos terrain — terrain unique to Mars — that generally appears formed by such processes, I find few outright obvious glacial features in this cropped portion or in the full image.
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The barren and icy northern lowland plains of Mars

The barren and icy northern lowland plains of Mars
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Cool image time! The picture to the right, cropped and sharpened to post here, was taken on January 2, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). Taken to fill a gap in the camera’s planned image schedule in order to maintain its temperature, the location was in this sense picked not for any particular scientific research project, but because the camera team decided they might find something interesting at this spot.

What they found is a vast flat plain of polygons, a feature found frequently on the surface of Mars and thought to be formed from processes similar to the drying that creates similar polygon cracks in dried mud here on Earth. In this case, the cracks are almost certainly in ice. As Colin Dundas of the U.S. Geological Survey’s Astrogeology Science Center in Arizona explained to me previously,
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Layers upon layers on Mars

Layers on Mars
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Today’s cool image once again illustrates that the geology of Mars will almost certainly center on a study of layers, as increasingly the orbital and rover images are telling us that the red planet is covered with innumerable layers, one after another, each created by another cycle, some seasonal, some global, and some related to climate and the planet’s fluctuating rotation tilt as well as its orbit around the Sun. And some might also be random volcanic events, unrelated to the cycles.

The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on October 10, 2022 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). Labeled by the science team “Layering in western Arabia Terra”, this section only shows a small amount of the layering visible in the full image. From east to west the ground rises in a series of terraces, each representing a different layer of distinct geology.
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Meandering ridges in Greg Crater

Meandering ridges in Greg Crater
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Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on November 29, 2022 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows what the scientists label “curved ridges.”

These might be inverted channels, the beds on which either water or ice flowed, compacting it down so that it became very resistant to erosion, and thus remains when the surrounding terrain was worn away. However, none of them seem to follow any grade. A more likely explanation is that these are ancient moraines, the debris pile pushed ahead of a glacier and then left behind when the glacier goes away.

The location is the reason I favor this explanation.
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Soft Martian buttes

Soft Martian buttes
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Cool image time! The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on January 1, 2023 by the high resolution camera on Mars Reconnaissance Orbiter to fill a gap in its shooting schedule so that the scientists could maintain the camera at its proper temperature.

In other words, the picture was not taken as part of any particular research project. Its target was in a sense chosen almost at random, though the science team always tries to find something of interest in such situations. In this case I think they succeeded, as these soft terraced buttes illustrate well the alien nature of Mars. The ground is barren, with absolutely no evidence of any life, and it appears that the buttes have been softened and eroded by eons of wind action. You can see evidence of this by the handful of dust devil tracks that cross the buttes.

There is more.
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Cliffs inside 285-mile-wide Schiaparelli Crater on Mars

Cliffs inside Schiaparelli Crater
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Cool image time! The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on December 2, 2022 by the high resolution camera on Mars Reconnaissance Orbiter (MRO), and was labeled by the science team as showing “dramatic cliffs and swirls in mound-skirting unit.”

I estimate the tallest point of this cliff butte to be somewhere between 500 and 800 feet high. And while the cliff is what first attracts the eye, one mustn’t ignore the vast amounts of dust and sand that cover everything here. The small teardrop-shaped buttes on the upper plateau suggest the prevailing wind direction there is from the north to the south. However, the north-south orientation of the ripple dunes on the floor below suggests that the prevailing wind direction below the cliff is east-west. Explaining how the topography could so quickly change the prevailing wind direction is beyond my skill.

The swirls mentioned by the scientists can be seen at the top of the cliff (on the left) and just below its base, in areas where there appears to be less dust. Those swirls reveal the many geological layers here.
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Splashed lava from a Martian impact

Splashed lava from a Martian impact
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Almost always it is impossible to understand a high resolution image from Mars Reconnaissance Orbiter (MRO) unless you also take a wider view. Today’s cool image to the right, rotated, cropped, reduced, and sharpened to post here, is a perfect example.

Taken on January 6, 2023, it shows what the science team labeled as a “rocky deposit on crater floor.” To my eye however none of this appeared tremendously rocky. Instead, what I saw was a curved and layered flow feature whose ancient age was suggested by the many later craters scattered across its surface.

Still, its origin was unclear. It isn’t ice, not only because of its apparent resistance from disturbance from those later crater impacts but because it is located at about 20 degrees north latitude, in the dry equatorial regions of Mars. If lava, what is its source? As I noted, a wider look was necessary to answer that question.
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The endless volcanic ash of Mars’ Medusae Fossae Formation

The endless volcanic ash of Mars' Medusae Fossae Formation
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Cool image time! The picture to the right, cropped, reduced, and enhanced to post here, was taken on January 6, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO), and shows a small but typical area of the Medusae Fossae Formation, what is thought to be the largest volcanic ash deposit on Mars.

The picture itself was a “terrain sample,” taken by the MRO science team not as part of any specific research but to fill a gap in the camera’s schedule so as to maintain its temperature. The terrain itself looks like a field of sand that someone had run a fine comb across. In this case, the comb was the winds of Mars, prevailing from the southeast to the northwest. The crescent-like divots in the picture’s lower right are probably caused by some hard underground feature that the winds cannot blow away. Instead, it blows around, like water in rapids flowing around a rock, and takes the ash with it as it does so.
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“What the heck?!” swirls on Mars


Click for original image.

Time for another “What the heck?!” image on Mars. The picture to the right, cropped to post here, was taken on January 6, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It is what the science team calls a “terrain sample,” which means it wasn’t taken as part of any specific scientific investigation and requested by a scientist. Instead, it was taken to fill a gap in MRO’s schedule. In order to maintain the camera’s proper temperature it is necessary for it to take regular pictures, and sometimes if there is a gap between requested images the science team picks something almost at random to fill the gap.

Sometimes the picture results in something relatively uninteresting. More often they try to pick something intriguing but not yet of interest to any particular researcher. With today’s cool image they certainly found something intriguing, so much so that I haven’t the faintest idea what is going on here.

Clearly, the tan swirls lie on the higher topology, and could be dust covered. The darker hollows in between could be darker because they are so, or because they are in shadow.
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A glacial river on Mars

A glacial river on Mars
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Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on November 1, 2022 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows a wonderful example of a glacier-filled canyon on Mars, the ice apparently flowing both along and around mesas as it carves its way downhill.

I think the downhill grade here is to the north, but this could be wrong for the two side canyons on the main canyon’s north side.

Not only is the material in the canyon likely ice, covered with a protective layer of trapped dust and ash that makes the glacier surface look so smooth, the mesa tops are likely impregnated with ice as well. The mesas however have little dust, so the plateaus have a mottled stippled look likely caused by sublimation of that underground ice.

The location of these canyons explains the presence of ice.
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Cracked ash-filled Martian terrain

Cracked ash-filled fissures on Mars
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Cool image time! The photo to the right, cropped, reduced, and sharpened to post here, was taken on September 26, 2022 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). The science team labeled this “Possible Pit,” but other than a small dark stain on the rim of a crater north of the section cropped to the right, I could find nothing that even closely resembled a pit. More likely the scientists were referring to the large circular depression in the top center of this picture. It does not at first glance look like a crater, as it has no obvious rim. In fact, almost none of the circular depressions in this image look like craters, as almost none have uplifted rims.

However, it is not clear what caused these dust-filled fractures as well as the image’s many circular depressions. The location, as indicated by the overview map below, does not really help.
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Terraced serrated layered mesas on Mars

Terraced mesas on Mars
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Cool image time! The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on November 19, 2022 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows a collection of terraced mesas covered with dust of a variety of colors.

The bluish colors suggest exposed bedrock, while the different shades of tan suggest areas covered by dust and volcanic ash. That the tan areas are likely dust is strengthened in that it is found between and on these rough mesas, where dunes are also seen. The dust gets blown in but gets trapped there.

The tan colors however could also indicate different types of bedrock, especially because different terraces seem to be of different shades. We will need more data to determine which, or whether this is a combination of all these geological processes.
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Dormant volcanic vent on Mars

Dormant volcanic vent on Mars
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Cool image time! The photo to the right, rotated, cropped, and reduced to post here, was taken on November 19, 2022 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows what the science team labels “Intersecting Fissures.”

These fissures stand out distinctly on this terrain. If you look at an MRO context camera image, showing a wider view, you can see that the surrounding plain is relatively featureless, with few craters. Except for some strange and inexplicable dark streaks close by to the east, some mottled but flat terrain to the north, and a long but very faint similar east-west fissure to the south, this runelike fissure is the only major topological feature for miles around.

That context camera image also shows that this fissure sits on top of a very faint bulge, with hints that material had flowed downhill from the fissure’s western and southern outlets. Located very close to the equator, it is unlikely that any of those flow features are glacial, and in fact they do not have that appearance in the context camera picture. Instead, they have the look of Martian lava, fast-moving and far less viscous than Earth-lava, and thus able to cover large areas much more quickly.

Thus, all the evidence says that this feature is a dormant volcanic vent, sitting on a flood lava plain. And the overview map below cements this conclusion.
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A Martian slope streak caused by a dust devil?

A Martian slope streak caused by a dust devil?
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Cool image time! The photo to the right, cropped, sharpened, and enhanced to post here, was taken on January 5, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows the interior slope of an unnamed 9-mile-wide crater, located just south of the Martian equator.

On that slope are several slope streaks, their dark color suggesting they are relatively recent. Also on that slope is the track of a dust devil that traversed that across slope. The track and the top of one of those streaks match, suggesting the dust devil might have caused the streak.

Did it? Maybe. This image was certainly taken to try to find out. Right now scientists do not know what causes slope streaks, a phenomenon unique to Mars. Though they look like avalanches, they do not change the topography at all, and sometimes flow over rises. If anything, they appear to be a stain on the surface, caused by some unknown process.
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Razor butte on Mars

Razor butte on Mars
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Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on November 18, 2022 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). The science team labeled this image “Inverted Channel and Possible Lake Deposits.” The sharp razor-like butte, which I estimate is about 200 to 400 feet high, is an example of the several inverted channels in the full image. The serrated-edged flat plateau at the top of this picture, one of several in the full image, is an example of those possible lake deposits.

Why do the scientists think a lake might have once been here? Located at 8 degrees north latitude in the dry equatorial regions of Mars, there is almost certainly no near surface ice here now.

As always, the overview map provides the context, and a possible explanation.
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Dramatic layers in Valles Marineris

Dramatic layers in Valles Marineris
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Cool image time! The picture to the right, rotated, cropped, and sharpened to post here, was taken on December 28, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO), and shows one tiny section of the interior slope of the giant Martian canyon Valles Marineris.

The while layers are not made of frost or ice, because they are light tan, as per the color image. Thus, the alternating layers of dark and light indicate different layering events. The dark layers are probably major lava flood events with a lot of dark ash intermixed, while the tan layers were flood lava events with little dark ash.

The dark lines that cut across these layers are ripple dunes formed from dust that has accumulated inside Valles Marineris.
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Buried silo on Mars?

A buried silo on Mars?
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Cool image time! The picture to the right, rotated and cropped to post here, was taken on December 31, 2022 by the high resolution camera on Mars Reconnaissance Orbiter.

The headline is pure silliness, and should not be taken seriously. However, the geological feature is intriguing nonetheless. Its almost perfect circular shape suggests a partly buried or eroded crater, except that its consistent thickness, almost like a wall, does not match what the rims of any crater should look like. Crater rims are made up of ejected material pushed out during impact, and thus always include some chaotic features.

My guess is that this circular feature is volcanic in nature. Maybe this was once a caldera, and the circle indicates a final vent from which lava extruded and then solidified.

At least, that’s my story.

The feature is located in the southwest quadrant of Hellas Basin, the basement of Mars, at 49 degrees south latitude. While this also suggests that ice might help explain this, we must also remember that much of the geology in that basin remains unexplained. Thus, there is no reason not to add one more feature to the list.

That ain’t snow on Mars

That ain't snow on Mars
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Today’s cool image proves once again that you must never too quickly jump to any conclusions when you first look at a picture from space. The photo to the right, cropped, reduced, and sharpened to post here, was taken on November 24, 2022 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

At first glance it appears that those ridges are topped with patches of snow or frost. Not. What appears white in this black and white photo is immediately revealed to be light-colored dust in the color image.

According the label assigned to this image by the science team, these ridges represent layers, likely tilted steeply so that when exposed they form the layered cliff edges where that light dust has now gathered.

The overview map below provides further evidence that the white patches are dust, not snow.
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Glaciers or taffy on Mars?

Glaciers of taffy on Mars?
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Cool image time! The photo to the right, rotated, cropped, reduced, and sharpened to post here, was taken on November 28, 2022 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It was released on January 4, 2023 as a captioned image, with this caption by Alfred McEwen of the Lunar & Planetary Laboratory in Arizona:

The floor of the Hellas impact basin, the lowest elevation on Mars, remains poorly explored because haze often blocks it from view. However, we recently got a clear image, revealing the strange banded terrain. These bands may be layers or flow bands or both.

At first glance, these bands reminded me of the many glaciers found on Mars. McEwen however is being properly vague about the nature of these features, for a number of reasons illustrated by the overview map below.
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A Martian bear!

A Martian bear!
Click for original image. Full image here.

Silly image time! Today the science team for the high resolution camera on Mars Reconnaissance Orbiter posted the photo to the right, which I have cropped, reduced, and annotated to post here. It was taken on December 12, 2022, and was rotated so that north is to the right in order to make its resemblance to a bear’s face obvious. As noted in the caption by Alfred McEwen of the Lunar & Planetary Laboratory in Arizona:

There’s a hill with a V-shaped collapse structure (the nose), two craters (the eyes), and a circular fracture pattern (the head). The circular fracture pattern might be due to the settling of a deposit over a buried impact crater. Maybe the nose is a volcanic or mud vent and the deposit could be lava or mud flows?

Maybe just grin and bear it.

If you have red-green glasses you can see a 3D anaglyph of this image here. The feature itself is located in the southern cratered highlands of Mars at 41 degrees south latitude, so the presence of near surface ice that would cause a mud volcano is definitely possible.

A dry lakebed on Mars?

Evidence of a past lake in a crater on Mars
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Today’s cool image illustrates in some ways the uncertainty of science. The photo to the right, rotated, cropped, reduced, and sharpened to post here, was taken on December 1, 2022 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). The science team intriguingly labeled it “Small Candidate Lake Deposit Downstream of Alluvial Fan.” I am not sure what they consider that lake deposit in the full image, so I have focused on the area of stucco-like ground, which resembles bedrock that has been corroded by some water process.

This area is just to the east of the central peaks of an unnamed 25-mile-wide crater in the southern cratered highlands. Many of the craters in this region are believed by scientists to have once harbored lakes formed by run-off from the glaciers that once existed on the craters’ inner rim. In this case it appears this stucco area is the head of an alluvial fan, coming down from the crater’s central peaks. You can see its beginning in this MRO high resolution image of the central peaks, taken in November 2016. As defined geologically,

An aluvial fan is an accumulation of sediments that fans outwards from a concentrated source of sediments, such as a narrow canyon emerging from an escarpment. They are characteristic of mountainous terrain in arid to semiarid climates, but are also found in more humid environments subject to intense rainfall and in areas of modern glaciation.

In this case the terrain is now arid, but shows evidence it once was icy wet.
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Martian crater with mound of ice? mud? hardened sand?

Crater with mound
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Cool image time! The photo to the right, cropped to post here, was taken on October 31, 2022 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows a small 4,000-foot-wide crater that is practically filled with a smooth, almost perfectly spherical mound, with the rest of the crater interior filled with sand dunes and what appears to be glacial debris.

Is that mound also glacial debris, covered with a layer of dirt and dust to protect it? If so, one wonders how the ice ended up in this shape. There are other craters with similar mounds in this region, all suggesting glacial debris but with the same question. Craters with lots of near surface ice in this region more often have a squishy blobby look.

Is the mound instead possibly mud, expressing the existence of a mud/ice volcano? If so, it shows no central pit or caldera, which is typical of such things.

Is it hardened sand? Martian dust that gets blown into craters generally gets trapped there, building up over time. If so, however, why does it have a smooth almost perfectly rounded shape? The ripple sand dunes surrounding it are more like what you would expect.

The small craters on the mound also tell us that it is hardened and old, no matter what it is made of.
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The youngest flood lava on Mars, flowing past a crater

Crater with lava flow
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Cool image time! The photo to the right, rotated, cropped, reduced to post here, was taken on December 3, 2022 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

The title given to this image by the MRO science team is “Upstream Edge of Crater in Athabasca Valles.” The crater itself is a pedestal crater, uplifted from the surrounding terrain because it was more resistant to erosion.

The material to the east of the crater’s rim definitely appears to have flow characteristics, but is it wet mud, glacial ice, or lava?

To figure this out we need as always some context. The latitude, 8 degrees north, immediately eliminates mud or glacial material. This location is in the dry equatorial regions of Mars, where no near surface ice has yet been found. Thus, the flow features are likely hardened lava.

What direction however was the flow? Was it flowing to the north, widening as it moved past the pedestal crater? Or was it to the south, narrowing as it pushed past that crater? To answer this question we need to widen our view.
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Machete Mesa on Mars

Machete Mesa on Mars
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Cool image time! The picture to the right, cropped to post here, was taken on November 30, 2022 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows a variety of ridges in a region of Mars called Arabia Terra, which is also the largest transition zone between the Martian southern cratered highlands and the northern lowland plains.

While this picture illustrates some nice geological facts about Mars (see below), I post it simply because of the dramatic sharpness of the ridge on top of the mesa, which I guess is several hundred feet high, but only a few feet across, at most, at its peak. A hike along this ridgeline would be a truly thrilling experience, one that the future human settlers on Mars will almost certainly find irresistible. Put this location on your planned tourist maps of Mars. It will likely be an oft-visited site.
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The sea of dunes surrounding the Martian north pole

The sea of dunes surrounding the Martian north pole
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Cool image time! The photo to the right, rotated, cropped, and reduced to post here, was taken on December 5, 2022 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows a collection of wormlike dunes located in the giant sea of dunes that surrounds the Martian north pole ice cap.

North is to the top. The season when this picture was taken was northern winter. The Sun is barely above the horizon, only 8 degrees high, and shining from the southeast. Because it is winter it is also dust season, making the atmosphere hazy and thus making the light soft. No distinct shadows, except that the sides of the dunes facing away from the Sun are darkly shadowed.

The consistent orientation of the dunes suggests that the prevailing winds blow from the northeast to create the steep-sided alcoves. The wind however might not be the only factor to form these dunes.
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A Martian river canyon?

A Martian river canyon?
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Today’s cool image highlights the biggest mystery of Mars that has baffled scientists since the first good pictures of its surface were taken in the early 1970s by the Mariner 9 orbiter. The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on October 24, 2022 by the high resolution camera on Mars Reconnaissance Orbiter (MRO), and shows a very small segment of the 400-mile-long meandering canyon on Mars called Nigal Vallis. From the Wikipedia page:

The western half of Nirgal Vallis is a branched system, but the eastern half is a tightly sinuous, deeply entrenched valley. Nirgal Vallis ends at Uzboi Vallis. Tributaries are very short and end in steep-walled valley heads, often called “amphitheater-headed valleys.”

We can see one of those short tributaries on the image’s left edge. The overview maps below provide a wider view of this entire canyon.
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