Tag: Mars

Recent impact on Mars

1:06 pm

Recent impact on Mars
Click for full image.

Cool image time! While finding recent impacts on Mars is not that unusual, the image to the right, found among the November image download from the high resolution camera on Mars Reconnaissance Orbiter (MRO), was dramatic enough that I decided that more people besides planetary scientists should see it. For scale the photograph is exactly 500 meters wide.

The photograph, taken September 26, 2019, also illustrates all the typical aspects of impact craters, and how they change the landscape.

This impact took place sometime between July 17, 2012 and January 4, 2018. We know this because it wasn’t there in a low-resolution image taken by the wide angle survey camera on MRO on the first date but was there when that same camera took another picture on the second date. Below is a side-by-side comparison of that July 17, 2012 image with the high resolution 2019 image above.
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Islands of ice on Mars and Pluto

12:54 pm

Ice-filled craters near Martian south pole

In a paper published today in the Journal of Geophysical Research: Planets, scientists describe the identification of 31 ice-filled craters in the high southern latitudes of Mars. The map to the right, from their paper, shows the locations of these craters. The scientists also took a look at Pluto, and found five craters there that had similar features, though these were likely filled with frozen nitrogen, not water ice.

From their abstract:

These new 31 ice deposits represent an inventory of more than 10 trillion cubic meters of solid water, similar to but greater in number and volume than previously studied features near the north pole. Similar features of nitrogen ice may exist in craters on Pluto, suggesting that craters are a favorable location for the accumulation or preservation of ices throughout the Solar System. [emphasis mine]

These results are reinforced by the existence of glacial features found in numerous Martian craters at much lower latitudes, as well as the ice suspected to exist in the permanently shadowed craters on the Moon and Mercury. The processes that put the ice there on these different planets might be fundamentally different, but the results are the same: Ice accumulating within craters.

One aspect of these high latitude craters that remains somewhat unexplained is their asymmetrical distribution around the south pole, favoring the side of the planet south of Mars’ giant volcanoes. Moreover, in looking at the ice deposits within these craters the scientists found that the ice seemed to lie off-center within the craters, favoring a similar direction.

Based on the available data, the scientists theorize that the most likely cause of this asymmetric off-center pattern is wind. From their paper:

Basic physical arguments, mesoscale atmospheric models, and geomorphological observations predict deflection of winds emanating from the south pole by the Coriolis Force. Such deflection results in a general westward trend of winds (i.e., easterlies) in the south polar regions outside the [south pole cap], matching the [ice-filled crater] offsets we observe.

This correlation implies that wind is important in … formation and/or evolution [of craters with ice]. For the case where winds control [their] formation, katabatic winds may travel down the east side of crater walls and preferentially deposit ice on the west side of the crater via orographic precipitation as they flow up the west crater wall. This mechanism thus favors local accumulation of ice within craters.

I find it fascinating that the location of ice within craters on Mars might indirectly provide scientists with information about the planet’s global weather patterns. This unexpected connection highlights the need to dismiss no data or feature in trying to understand planetary formation. Unlikely things might answer our questions.

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A journey into the depths of Valles Marineris

1:20 pm

Valles Marineris

Cool image time! Rather than start with the cool image, let’s begin with the long view. To the right is a wide mosaic of Valles Marineris on Mars, the largest known canyon in the solar system. About 2,500 miles long and 400 miles wide, this canyon is so large that it would cover most of the United States if put on Earth. The Grand Canyon, 500 miles long by 19 miles wide, could easily fit within it and not be noticed. In depth Valles Marineris is equally impressive, with a depth of more than four miles, about four times deeper than the Grand Canyon.

A closer view of the central regions of Valles Marineris

The white cross in the mosaic above is where we are heading. You can see it as the white box in the zoomed in overview to the right. This central part of Valles Marineris is named East Melas Chasma, and the red boxes indicate locations where the high resolution camera of Mars Reconnaissance Orbiter (MRO) has already taken images.

As you can see, we do not yet have many high resolution images of this part of the canyon floor. The white box is the most recent image, and is the subject of today’s post.
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Both methane and oxygen fluctuate in unison seasonally in Gale Crater

10:04 am

The uncertainty of science: According to a new science paper, data from Curiosity on Mars has now found that both methane and oxygen fluctuate in unison seasonally in Gale Crater.

From the paper’s abstract:

[T]he annual average composition in Gale Crater was measured as 95.1% carbon dioxide, 2.59% nitrogen, 1.94% argon, 0.161% oxygen, and 0.058% carbon monoxide. However, the abundances of some of these gases were observed to vary up to 40% throughout the year due to the seasonal cycle. Nitrogen and argon follow the pressure changes, but with a delay, indicating that transport of the atmosphere from pole to pole occurs on faster timescales than mixing of the components. Oxygen has been observed to show significant seasonal and year‐to‐year variability, suggesting an unknown atmospheric or surface process at work. These data can be used to better understand how the surface and atmosphere interact as we search for signs of habitability.

The data shows that the unexpected and so far unexplained seasonal oxygen fluctuation appears to track the same seasonal methane fluctuations. While biology could cause this signature, so could geological processes, though neither can produce these fluctuations easily.

Meanwhile, adding to the uncertainty were results from the two European orbiters, Mars Express and Trace Gas Orbiter. Both have failed to detect a June 19, 2019 dramatic spike in methane that had been measured by Curiosity.

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China unveils Mars lander during landing simulation test

9:44 am

The new colonial movement: China today unveiled to the international press its first prototype Mars lander, showing it attempting a simulated controlled descent on a gigantic test stand.

The demonstration of hovering, obstacle avoidance and deceleration capabilities was conducted at a site outside Beijing simulating conditions on the Red Planet, where the pull of gravity is about one-third that of Earth.

China plans to launch a lander and rover to Mars next year to explore parts of the planet in detail.

This is the first time I have heard anything about China sending a lander/rover to Mars in 2020. Previously the reports had discussed only sending an orbiter.

I have embedded video of the test below the fold. It shows the prototype hanging by many wires from the test stand, then dropping quickly, with its engine firing, before stopping suddenly, followed by an engine burst. While impressive, it did not strike me that China is even close to sending this spacecraft to Mars. The test only proved the spacecraft’s ability to do some maneuvering during descent. It did not show that it could land.

That the project’s designer said that landing would take “about seven minutes” also suggests that they are copying the techniques used by JPL to land Curiosity. Considering that JPL’s computers have been repeatedly hacked, including some hacks identified as coming from China, it would not surprise me if China has simply stolen those techniques.

I still expect them to launch an orbiter to Mars in 2020. Whether they also send a lander and rover remains to be seen.
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SpaceX completes 1st round of Starship’s Mars landing site images

1:31 pm

All locations photographed of the candidate landing region for SpaceX's planned Mars missions

On August 28, 2019 I broke the story that SpaceX is beginning to obtain images of candidate Starship landing sites from Mars Reconnaissance Orbiter (MRO).

It now appears that SpaceX has completed its first round of Starship requests from MRO. In the image releases from Mars Reconnaissance Orbiter (MRO) since September, only three new Starship locations were taken, and all three were the unreleased candidate sites I noted in my September 16, 2019 update.

Below is the full list of all of the Starship images, their locations indicated on the map above by the numbered white boxes:

With the release of these last photographs, the initial list of proposed images of candidate Starship landing sites on Mars has apparently been completed. No additional images at any other locations appear to have been suggested. The MRO science team has taken stereo images of each one of the nine locations, eight of which were in Amazonis Planitia, and one in Phlegra Montes.

This however is not the first round of pictures requested by SpaceX of the Arcadia Planitia region in connection with the company’s desire to land spacecraft on Mars.
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Polygons on Mars

1:44 pm

Scallops and polygons on Mars
Click for full image.

Cool image time! The photograph on the right, cropped to post here, was taken on September 25, 2019 by the high resolution camera on Mars Reconnaissance Orbiter (MRO) and made public in its November image release. It shows the weird but very typical scalloped terrain, with its adjacent polygon pattern of fractures, found routinely in the northern lowland plains of Utopia Planitia on Mars. From an earlier captioned image from 2006 of these same features:

The scalloped depressions are typical features; a smooth layered terrain located between 40 and 60 degrees in both hemispheres. Scalloped depressions probably form by removal of ice-rich subsurface material by sublimation (ice transforming directly from a solid to a gaseous state), a process that may still be active today. Isolated scalloped depressions generally have a steep pole-facing scarp and a gentler equator-facing slope. This asymmetry is interpreted as being the result of difference in solar heating. Scalloped depressions may coalesce, leading to the formation of large areas of pitted terrain.

The polygonal pattern of fractures resembles permafrost polygons that form in terrestrial polar and high alpine regions by seasonal-to-annual contraction of the permafrost (permanently frozen ground). On Earth, such polygons indicate the presence of ground ice.

On Earth these polygons are most often seen in mud, usually suggesting a drying process where the ground contracts with the lose of fluid. On Mars the cracks probably also form from contraction, but not by the lose of fluid but the lose of water ice as it sublimates into a gas.

These polygons and scallops illustrate an important feature of Mars’ vast northern plains. On large scales these plains appear flat and featureless. Up close however many many strange features, like the polygons and scallops in this image, come into view.
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Mars’ seasonally vanishing carbon dioxide polar cap

1:36 pm

Buzzell dunes, March 19, 2019
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Since the onset of the Martian spring in the northern hemisphere back in March of this year, scientists have been busy using the high resolution camera on Mars Reconnaissance Orbiter (MRO) to monitor the expected sublimation and disappearance of the cap of dry ice that falls as snow to become a winter layer mantling both the more permanent icecap of water 7,000 feet deep as well as the giant dune sand seas that surround that northern icecap.

The image on the right was first posted here on Behind the Black on June 6, 2019 as part of a long article describing that northern polar icecap and its annual evolution. It shows a set of dunes that Candice Hansen of the Planetary Science Institute in Arizona, who requested the image, has dubbed “Buzzell.” When that picture was taken in March, the frozen dry ice layer of translucent carbon dioxide still coated the dunes. The image’s darkness is because the Sun has just begun to rise above the horizon at this very high latitude location (84 degrees). The circular feature is likely a buried ancient crater, with the streaks indicating the prevailing wind direction blowing both sand and frost about.

On August 9, 2019 I provided an update on this monitoring, when new images of this same location were downloaded from MRO in April and June. MRO has now taken a new image of Buzzell, on October 2, 2019. Below the fold are all these images so that you can see the sublimation and disappearance of that dry ice layer over time.
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New InSight image of mole shows collapse of hole

10:56 am

View of InSight drill hole
Click for full movie.

The InSight science image has lifted the lander’s rover arm off the drill hole and taken a new series of images in an effort to discover what caused the mole to pop out during its most recent drilling effort.

The image to the right, cropped to post here, was the first in a short movie made from all the images taken over the course of a day. The sequence shows the change in shadows, which helps define the situation in the hole.

This image however I think tells all. It shows that the walls of the hole have collapsed all around the mole, widening it further. It also shows that, once the mole popped out to lean sideways against the left wall, much of that material then fell into the hole, refilling it. These facts are very evident when today’s image is compared with this image from October, taken prior to the most recent drilling effort. The hole has become much wider, there is more material inside it, and the mole is now much farther out.

All these facts bode ill for the mole ever succeeding in drilling down the planned fifteen or so feet to insert a heat probe into the interior of Mars in order to take the first ever measure of the planet’s interior.

An overall assessment of this NASA mission is not very positive. The contribution from its international partners is especially bad. The mission was launched two years late because the French effort to build the seismometer failed. NASA had to subsequently give the job to JPL to get it done. Now the heat sensor is a failure, because the German-built mole has failed to get the heat sensor where it needs to be.

The seismometer and heat sensor were InSight’s only science instruments. This means that we will likely only get results from one.

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Sightseeing Central Butte on Mars

11:38 am

Central Butte in foothills of Mt Sharp

Overview showing perspective of panorama

Curiosity has now roved to the very foot of Central Butte, where it has been taking close-up and panorama images of the butte and its geological layers. The panorama above was created from three Curiosity navigation images taken on Sol 2577 (November 6, 2019), here, here, and here.

The overview on the right, based on Curiosity’s position about ten sols ago slightly farther from the butte, still indicates roughly with the yellow lines the area photographed in this panorama. The dotted red line indicates Curiosity’s initial planned route.

Following that route Curiosity will eventually climb up onto the plateau beyond this butte, approaching that higher terrain farther to the west. Once they do, however, they will no longer have access to the geological layers below the surface. Central Butte gives them a window into those layers, which is why they are going to spend some time at this location, first by taking a few sols looking at the butte at this point, then circling around to study its back side.

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Rover update: October 28, 2019

1:05 pm

Summary: Curiosity finally on the move after several months drilling two adjacent holes in the clay unit. Yutu-2 continues roving west, has it now operates during its eleventh lunar day on the far side of the Moon.

For the updates in 2018 go here. For a full list of updates before February 8, 2018, go here.

Curiosity's present location in Gale Crater
Click for original full image.

Curiosity

For the overall context of Curiosity’s travels, see my March 2016 post, Pinpointing Curiosity’s location in Gale Crater.

I have not done any of my regular rover updates since May 30, 2019 because it was simpler to do individual updates for both Curiosity and Yutu-2, the only working rovers presently on other worlds. (If things had gone well, which they did not, we would have had two other lunar rovers in the past six months, one from Israel and one from India, but both crashed during landing.)

However, since Curiosity is finally on the move after spending several months at one location, where it drilled two holes in the clay unit (the material from one used in a wet cup experiment to look for organic life) it is time to update my readers on where Curiosity is and where it is heading.

The first image above and to the right is an annotated overview of Curiosity’s present position, moving south to a line of buttes which scientists have determined delineates the transition from the clay unit to a new geological layer they have dubbed the Greenheugh Pedimont. The yellow lines indicate the area seen in the panorama below, created from two photographs (here and here) taken by the rover’s navigation camera.
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InSight’s mole has popped out of its hole

8:35 am

InSight's mole, out of the ground
Click for full image.

In a setback for its renewed digging effort, the mole drill on InSight has apparently bounced out of its drilled hole during the most recent drilling, soon after engineers had increased the rate of hammer strokes.

The image to the right shows the mole, the white cylinder on the left, with the scoop of the robot arm mostly covering the hole in its effort to pin the mole in position.

“While digging this weekend the mole backed about halfway out of the ground,” the mission announced via a pair of tweets Oct. 27. “Preliminary assessment points to unexpected soil properties as the main reason.”

…The mission added that one possibility is soil is falling in front of the mole, filling the hole. “Team continues to look over the data and will have a plan in the next few days.”

Without question the alien and fluffy properties of the soil appears to be the problem. Based on how the mole is leaning, I wonder if the left wall of the hole began to widen and collapse, as had the rest of the hole during initial drilling, thus defeating the purpose of the robot arm’s effort to pin the mole in place.

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Ancient glacier flows on Mars

3:17 pm

Ancient glacial flow in Euripus Mons
Click for full image.

Cool image time! In the recent download of images from the high resolution camera of Mars Reconnaissance Orbiter (MRO), I found the image on the right, rotated, cropped, and reduced to post here. It shows an example of the many glacial flows coming off of the slopes of Euripus Mons, the sixteenth highest mountain on Mars.

We know these are glaciers because data from SHARAD, the ground-penetrating radar instrument MRO, has found significant clean ice below the surface, protected by a debris layer that insulates it. As planetary scientist Alfred McEwen of the Lunar & Planetary Laboratory in Arizona explained to me in a phone interview yesterday,

These are remnant glaciers. Basically they form like glaciers form. They are not active or if they are they are moving so extremely slowly that effectively they are not active.

If you look close, you can see that this particular glacier was made up of multiple flows, with the heads or moraines of each piled up where each flow ended. In addition, this overall glacier appears to have been a major conduit off the mountain, following a gap between more resistant ridges to the east and west.

The sequence of moraines suggest that when the glacier was active, it experienced alternating periods of growth and retreat, with the growth periods being shorter and shorter with time. As a result each new moraine was pushed less distance down the mountain as the previous one.

Euripus Mons is interesting in that it has a very large and distinct apron of material surrounding it, as shown in the overview image below.
» Read more

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Curiosity takes selfie next to two of its most important drill holes

3:04 pm

Curiosity and its most recent drill holes
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The Curiosity science team today released a beautiful mosaic of the rover, stitched from 57 different images. The photo at the right, cropped and reduced to post here, is the annotated version of that image. It shows the rover’s two most recent drill holes to the left. As the view looks away from Mount Sharp, you can see in the distance Vera Rubin Ridge, the floor of the crater, and its rim on the far horizon.

The two drill holes are significant because of the chemical experiment that Curiosity is subjecting the material from those holes.

The special chemistry experiment occurred on Sept. 24, 2019, after the rover placed the powderized sample from Glen Etive 2 into SAM. The portable lab contains 74 small cups used for testing samples. Most of the cups function as miniature ovens that heat the samples; SAM then “sniffs” the gases that bake off, looking for chemicals that hold clues about the Martian environment billions of years ago, when the planet was friendlier to microbial life.

But nine of SAM’s 74 cups are filled with solvents the rover can use for special “wet chemistry” experiments. These chemicals make it easier for SAM to detect certain carbon-based molecules important to the formation of life, called organic compounds.

Because there’s a limited number of wet-chemistry cups, the science team has been saving them for just the right conditions. In fact, the experiment at Glen Etive is only the second time Curiosity has performed wet chemistry since touching down on Mars in August 2012.

This time however was the first time they had used a wet chemistry cup on material from a drill hole. That they were able to do this at all is a testament to the brilliant innovative skills of the rover’s engineers. They had been holding off doing a wet chemistry analysis from drill hole material until they got to this point, but on the way the rover’s drill feed mechanism failed. It took more than a year of tests and experimentation before they figured out a way to bypass the feed mechanism by using the arm itself to push the drill bit into the ground. That rescue made possible the wet chemistry experiment that they initiated on September 24.

The results, which are eagerly awaited, won’t be available until next year, as it will take time for the scientists to analyze and publish their results.

Curiosity meanwhile has moved on, leaving this location where it had remained for several months to march in the past week southward back towards its long planned route up Mount Sharp.

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Big landslides on Mars might not require ice

1:49 pm

According to a new paper, scientists now think the biggest and longest landslides found on Mars might not require a base of ice on which it could slide such extensive distances.

The findings, published today in Nature Communications, show for the first time that the unique structures on Martian landslides from mountains several kilometres high could have formed at high speeds of up to 360 kilometres per hour due to underlying layers of unstable, fragmented rocks.

This challenges the idea that underlying layers of slippery ice can only explain such long vast ridges, which are found on landslides throughout the Solar System.

First author, PhD student Giulia Magnarini (UCL Earth Sciences), said: “Landslides on Earth, particularly those on top of glaciers, have been studied by scientists as a proxy for those on Mars because they show similarly shaped ridges and furrows, inferring that Martian landslides also depended on an icy substrate. “However, we’ve shown that ice is not a prerequisite for such geological structures on Mars, which can form on rough, rocky surfaces. This helps us better understand the shaping of Martian landscapes and has implications for how landslides form on other planetary bodies including Earth and the Moon.”

The lighter gravity of Mars, about one third of Earth’s, is part of the explanation, though many other factors are involved. Either way, this is one more data point in the evidence that the though geology on Mars might look like what we see on Earth, it is likely very different than we expect, due to the alien nature of Mars itself.

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Mars2020 budget overruns threatening other missions

11:18 am

The significant budget overruns for NASA’s Mars 2020 mission, now expected to exceed a billion dollars, could now pose a threat to other planetary projects.

The cost of Mars 2020 has been growing for a while. The initial proposed cost for the rover, when the mission was announced in 2012, was $1.5 billion. Six years on, a 2018 Government Accountability Office (GAO) report showed that the cost had soared to $2.46 billion. And in NASA’s latest budget, the overrun looks set to grow by as much as 15% (or about another $360 million) beyond that last 2018 estimate, although the latest numbers are yet to be confirmed.

The irony is that Mars 2020 was established by the Obama administration as part of its effort to significantly cut back on NASA’s entire planetary program. The idea was to save money by simply rebuilding Curiosity.

As is typical for these projects, the scientists pushed for cutting edge instruments, and it is these instruments that have caused the overages. Meanwhile, many of those 2012 cuts pushed by Obama never happened, or were simply funneled into different planetary projects that were approved later.

No one who is involved in any way with the U.S. government today knows anything about keeping their effort on budget and on time. No one. And the result is increasing debt and what will certainly be bankruptcy for everyone, at some point, thus causing everything to shut down.

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InSight’s digging problems reveal the alienness of Mars’ soil

9:01 am

Even as InSight’s mole shaft driller shows signs of working, its difficulties in digging into the Martian soil has revealed how truly alien that soil is from what we normally expect.

[U]nlike typical holes dug here on Earth, the one excavated by InSight’s mole has no lip of dirt around its rim, Hoffman said. “Where did the soil go?” he said. “Basically, it got pounded back into the ground, so it seems like it’s very cohesive, even though it’s very dusty.”

And this is a weird combination of characteristics, strongly suggesting that Mars dirt is alien in more ways than one. “The soil properties are very different than anything we’ve ever seen on Earth, which is already a very interesting result,” Hoffman said.

That the soil of Mars is alien should not be a surprise. The planet’s dusty nature, combined with its light gravity and lack of life, practically guaranteed that the soil would have different and unexpected properties. What is disturbing is that it appears this likelihood was not considered in the slightest by the German engineers who designed the mole for digging.

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Lava-draped terrain on Mars

1:58 pm

Lava surrounding hill and partly covering crater
Click for full image.

Hill surrounded by lava flows
Click for full image.

Cool image time! Continuing this week’s series of lava-related images from Mars (previous posts here, here, and here), today’s post is ironically the first to actually show lava flows.

The two images to the right, reduced and cropped to post here, are sections taken from an uncaptioned picture, titled “Lava-Draped Surface in Cerberus Palus” and found in the most recent download from the high resolution camera on Mars Reconnaissance Orbiter (MRO).

It is obvious why the MRO scientists gave this image this title. The hills in both pictures clearly seem to stand up like islands in a surrounding sea of frozen lava. Older craters, created prior to the lava flow, are partly obscured by the lava flows, their interior floors filled and their rims broken as the lava flooded this region.

Nor are these the only high points captured in the image that this flood of lava inundated. If you look at the full image there is even a low mound where it appears the surrounding lava flood worked its way up the hill’s gently sloping flanks only to freeze just before it completely covered the top of the mound.

The location of this image, shown by the red box in the overview map below and to the right, gives us a hint where the lava came from, though the distances involved to the nearest giant volcano, Elysium Mons, are so large it is likely that this flow is not directly linked to that volcano.
» Read more

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Sinkholes on Mars

2:01 pm

Collapse pit on Mars
Click for full image.

Cool image time! In this week’s exploration of Martian geology that is reminiscent of Earth-based lava geology, today’s image is of a collapse pit in Ceraunius Fossae, the vast region of north-south fissures found to the south of the volcano Alba Mons. The photo to the right, cropped to post here, zooms in on that pit.

The picture was part of the most recent image release from the high resolution camera on Mars Reconnaissance Orbiter (MRO). What makes it especially interesting is the sharpness of its rim, in comparison to the collapse channel to the east. This suggests the pit is younger and fresher than the channel, and happened more recently. This also implies that the voids below the ground in which the surface is sinking are either still there, or due to on-going processes might be still be forming (like caves are on Earth).

For example, if there is underground ice, temperature changes or even thermal heat from the nearby giant volcanoes could melt that underground ice periodically, allowing it to flow and erode the surrounding material, forming voids. That this pit is located at 30 degrees north latitude, just inside the northern hemisphere band where glaciers are found, adds weight to this possibility.

The image below, reduced and rotated so that north is to the left, shows the entire sequence of collapse channels, with the more distinct pit from above in the bottom center of the picture.
» Read more

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A discontinuous Martian channel

12:57 pm

Discontinuous channel near Olympica Fossae
Click for full image.

Close-up of channel

Time for more strange Martian geology! As I said in my post yesterday of a cool image of skylights into what might be a Martian lava tube, this is lava week on Behind the Black. The image at the right, rotated, reduced, and cropped to post here, is similar to yesterday’s photograph, showing a line of sinks and depressions that strongly suggest the existence of an underground lava tube.

The problem with this theory is that at present we really have no idea what flowed here. It could have been lava, but it also could have been mud, water, ice, or some as yet unimagined Martian geological process.

The image was part of the most recent image release from the high resolution camera on Mars Reconnaissance Orbiter (MRO), and was uncaptioned. The top image shows the whole channel as captured by the photograph, with the white box indicating the area covered by the second image, posted here at full resolution.

Though the overall slope of the terrain here is downhill to the west, the grade is relatively shallow, so there is no guarantee that the local slope of this particular channel follows that trend. Downhill could be either to the west or the east.

The reason I favor lava (as an amateur geologist) is the location of this channel, as shown in the overview map below and to the right.
» Read more

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