Martian pit on top of Martian dome
Click for full image.
Cool image time! The photo to the right, cropped and reduced to post here, was taken on March 7, 2021 by the high resolution camera on Mars Reconnaissance Orbiter (MRO) and was simply labeled “Pit on Top of Dome in Promethei Terra.”
The cropped section to the right shows one of two such pits visible on the entire image. Promethei Terra is a large 2,000 mile long cratered region due east from Hellas Basin, the deepest large region on Mars.
What caused these pits? The known facts provide clues, but do not really solve the mystery.
First, this image is located in the southern cratered highlands at 45 degrees south latitude. Thus, it is not surprising that it resembles similar terrain in the northern lowlands that suggests an ice layer very close to the surface.
Second, the stippled terrain to the east of the dome is reminiscent of brain terrain, an as-yet unexplained geological feature seen in the latitudes above 30 degrees both north and south that is associated with areas where glacial features are found.
Third, the crater in the image resembles similar craters found in the northern lowlands that appear filled with ice. That this filling seems to favor the crater’s northern interior, which will be more shadowed most of the year, lends weight to this hypothesis.
Finally, this image is located about 175 miles southeast of Reull Valles, a canyon feeding into Hellas Basin where many glacial features are found. It is also not far north of the same region where many ice scarps have been identified, cliff faces with visible underground ice layers exposed.
So, there is likely ice under the ground here and possibly close to the surface, which suggests the pit and dome might possibly be an ice volcano.
Yet, maybe not. Why should there be an ice volcano here and not elsewhere? What causes the ice to be forced upward? Most of the time in these Martian glacial regions the ice instead flows downward, following the grade, like water and ice usually do.
Then there is the faint circular feature to the southwest of the pit that is also about the same size. This suggests an impact crater that has been most filled or eroded over time. Maybe the dome is made up of some pedestal craters, now covered with ice. Under this scenario, the impacts occurred, then over time the surrounding terrain eroded away leaving the hardened impact craters as pedestals. Then a large amount of ice was deposited on top, hiding the older craters entirely. Now that ice is sublimating away slowly, and the pit is a sink located over the center of one of those hidden pedestal craters.
Sounds good? Well, I gotta million of ’em! And all my theories are worth about as much as the electrons they are written on. More data is needed, including some in situ observations and even some core samples. Only then will we be able to form truly reliable theories as to what happened here.
Readers!
Please consider supporting my work here at Behind the Black. Your support allows me the freedom and ability to analyze objectively the ongoing renaissance in space, as well as the cultural changes -- for good or ill -- that are happening across America. Fourteen years ago I wrote that SLS and Orion were a bad ideas, a waste of money, would be years behind schedule, and better replaced by commercial private enterprise. Only now does it appear that Washington might finally recognize this reality.
In 2020 when the world panicked over COVID I wrote that the panic was unnecessary, that the virus was apparently simply a variation of the flu, that masks were not simply pointless but if worn incorrectly were a health threat, that the lockdowns were a disaster and did nothing to stop the spread of COVID. Only in the past year have some of our so-called experts in the health field have begun to recognize these facts.
Your help allows me to do this kind of intelligent analysis. I take no advertising or sponsors, so my reporting isn't influenced by donations by established space or drug companies. Instead, I rely entirely on donations and subscriptions from my readers, which gives me the freedom to write what I think, unencumbered by outside influences.
You can support me either by giving a one-time contribution or a regular subscription. There are four ways of doing so:
1. Zelle: This is the only internet method that charges no fees. All you have to do is use the Zelle link at your internet bank and give my name and email address (zimmerman at nasw dot org). What you donate is what I get.
2. Patreon: Go to my website there and pick one of five monthly subscription amounts, or by making a one-time donation.
3. A Paypal Donation or subscription:
4. Donate by check, payable to Robert Zimmerman and mailed to
Behind The Black
c/o Robert Zimmerman
P.O.Box 1262
Cortaro, AZ 85652
You can also support me by buying one of my books, as noted in the boxes interspersed throughout the webpage or shown in the menu above.
Click for full image.
Cool image time! The photo to the right, cropped and reduced to post here, was taken on March 7, 2021 by the high resolution camera on Mars Reconnaissance Orbiter (MRO) and was simply labeled “Pit on Top of Dome in Promethei Terra.”
The cropped section to the right shows one of two such pits visible on the entire image. Promethei Terra is a large 2,000 mile long cratered region due east from Hellas Basin, the deepest large region on Mars.
What caused these pits? The known facts provide clues, but do not really solve the mystery.
First, this image is located in the southern cratered highlands at 45 degrees south latitude. Thus, it is not surprising that it resembles similar terrain in the northern lowlands that suggests an ice layer very close to the surface.
Second, the stippled terrain to the east of the dome is reminiscent of brain terrain, an as-yet unexplained geological feature seen in the latitudes above 30 degrees both north and south that is associated with areas where glacial features are found.
Third, the crater in the image resembles similar craters found in the northern lowlands that appear filled with ice. That this filling seems to favor the crater’s northern interior, which will be more shadowed most of the year, lends weight to this hypothesis.
Finally, this image is located about 175 miles southeast of Reull Valles, a canyon feeding into Hellas Basin where many glacial features are found. It is also not far north of the same region where many ice scarps have been identified, cliff faces with visible underground ice layers exposed.
So, there is likely ice under the ground here and possibly close to the surface, which suggests the pit and dome might possibly be an ice volcano.
Yet, maybe not. Why should there be an ice volcano here and not elsewhere? What causes the ice to be forced upward? Most of the time in these Martian glacial regions the ice instead flows downward, following the grade, like water and ice usually do.
Then there is the faint circular feature to the southwest of the pit that is also about the same size. This suggests an impact crater that has been most filled or eroded over time. Maybe the dome is made up of some pedestal craters, now covered with ice. Under this scenario, the impacts occurred, then over time the surrounding terrain eroded away leaving the hardened impact craters as pedestals. Then a large amount of ice was deposited on top, hiding the older craters entirely. Now that ice is sublimating away slowly, and the pit is a sink located over the center of one of those hidden pedestal craters.
Sounds good? Well, I gotta million of ’em! And all my theories are worth about as much as the electrons they are written on. More data is needed, including some in situ observations and even some core samples. Only then will we be able to form truly reliable theories as to what happened here.
Readers!
Please consider supporting my work here at Behind the Black. Your support allows me the freedom and ability to analyze objectively the ongoing renaissance in space, as well as the cultural changes -- for good or ill -- that are happening across America. Fourteen years ago I wrote that SLS and Orion were a bad ideas, a waste of money, would be years behind schedule, and better replaced by commercial private enterprise. Only now does it appear that Washington might finally recognize this reality.
In 2020 when the world panicked over COVID I wrote that the panic was unnecessary, that the virus was apparently simply a variation of the flu, that masks were not simply pointless but if worn incorrectly were a health threat, that the lockdowns were a disaster and did nothing to stop the spread of COVID. Only in the past year have some of our so-called experts in the health field have begun to recognize these facts.
Your help allows me to do this kind of intelligent analysis. I take no advertising or sponsors, so my reporting isn't influenced by donations by established space or drug companies. Instead, I rely entirely on donations and subscriptions from my readers, which gives me the freedom to write what I think, unencumbered by outside influences.
You can support me either by giving a one-time contribution or a regular subscription. There are four ways of doing so:
1. Zelle: This is the only internet method that charges no fees. All you have to do is use the Zelle link at your internet bank and give my name and email address (zimmerman at nasw dot org). What you donate is what I get.
2. Patreon: Go to my website there and pick one of five monthly subscription amounts, or by making a one-time donation.
3. A Paypal Donation or subscription:
4. Donate by check, payable to Robert Zimmerman and mailed to
Behind The Black
c/o Robert Zimmerman
P.O.Box 1262
Cortaro, AZ 85652
You can also support me by buying one of my books, as noted in the boxes interspersed throughout the webpage or shown in the menu above.
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