A bullseye on Mars
Click for full image.
Cool image time! In researching my piece last week on the glaciers of Mars I had wanted to include a picture of a typical concentric glacier-filled crater, the most widespread glacial feature on the Martian surface, found in a band at latitudes between 30 and 60 degrees. (You can see the example I found at the link above, near the end of the article.)
To find that picture I searched the Mars Reconnaissance Orbiter (MRO) archive. Among the images I found was a captioned image taken very early in MRO’s mission showing a crater with concentric rings very similar to the concentric glacial-filled craters. The image at the right is that crater, the image reduced and cropped to post here. As described in that caption,
Moving out from the crater center, the layers appear to be stair-stepped so that each layer is slightly lower than the previous one; the innermost layers are the youngest, deposited on top of a stack of sediments. The concentric pattern could be simply due to each layer being eroded slightly more than the one below it, but another factor may be the shape of the layers. If each layer draped over the interior of the crater and the region was eroded to a nearly flat surface, the layers would appear as a succession of rings. Topographic data of sufficient resolution would enable us to distinguish between these two models
Since this crater was located at on 1 degree south latitude, essentially at the Martian equator, if it was glacial it would be far south of those glacial bands, and in fact be the most equatorial of all. Based on the all the research I’ve reviewed on Martian glaciers, this shouldn’t glacial.
One clue that it was not glacial was the erosion pattern, with the highest feature at the crater’s center and the terraces descending concentrically outward to the crater’s rim. The glacial craters at higher latitude tended to be more flat, and seemed to instead descend toward the crater’s center.
The caption however did not say one way or the other. Moreover, it has been written back in 2007, before scientists had known much about the glacial features on Mars. If this was glacial it would be a big deal, as it was at the equator. I emailed Colin Dundas U.S. Geological Survey’s Astrogeology Science Center in Arizona, who wrote the caption and has been helpful previously. He confirmed the non-glacial nature of this crater.
That’s a different feature–it’s a set of rocky layers that lined the inside of an impact crater and were then planed off by erosion, producing a series of concentric rings. It’s distinct from the classic “concentric crater fill” that is due to ice creep and flow.
He also mentioned that there have been published reports of other equatorial craters that were ice-rich. I have located two stories suggesting the existence of glaciers close to the Martian equator.
- ‘Pack ice’ suggests frozen sea on Mars
- Analysis Sharpens Mars Hydrogen Map, Hinting Equatorial Water Ice
In both stories the presence of ice is only indirectly inferred. There is no direct evidence of water. This does not eliminate the possibility of equatorial Martian ice, but the science here remains very uncertain.
Meanwhile, the image above with its wedding cake mesa in the center of a crater remains quite fascinating. Assuming that the fill in the crater was once flat, and then eroded away to leave behind that central mesa, why has this erosion formed this concentric pattern? The theories mentioned in the caption are not very clear on this point. To repeat, the science is very uncertain.
The Martian landscape continues to amaze.
The support of my readers through the years has given 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. Four years ago, just before the 2020 election I wrote that Joe Biden's mental health was suspect. Only in this year has the propaganda mainstream media decided to recognize that basic fact.
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. Even today NASA and Congress refuse to 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.
Please consider supporting my work here at Behind the Black.
You can support me either by giving a one-time contribution or a regular subscription. There are five 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:
5. Donate by check, payable to Robert Zimmerman and mailed to
Behind The Black
c/o Robert Zimmerman
P.O.Box 1262
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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. And if you buy the books through the ebookit links, I get a larger cut and I get it sooner.
Click for full image.
Cool image time! In researching my piece last week on the glaciers of Mars I had wanted to include a picture of a typical concentric glacier-filled crater, the most widespread glacial feature on the Martian surface, found in a band at latitudes between 30 and 60 degrees. (You can see the example I found at the link above, near the end of the article.)
To find that picture I searched the Mars Reconnaissance Orbiter (MRO) archive. Among the images I found was a captioned image taken very early in MRO’s mission showing a crater with concentric rings very similar to the concentric glacial-filled craters. The image at the right is that crater, the image reduced and cropped to post here. As described in that caption,
Moving out from the crater center, the layers appear to be stair-stepped so that each layer is slightly lower than the previous one; the innermost layers are the youngest, deposited on top of a stack of sediments. The concentric pattern could be simply due to each layer being eroded slightly more than the one below it, but another factor may be the shape of the layers. If each layer draped over the interior of the crater and the region was eroded to a nearly flat surface, the layers would appear as a succession of rings. Topographic data of sufficient resolution would enable us to distinguish between these two models
Since this crater was located at on 1 degree south latitude, essentially at the Martian equator, if it was glacial it would be far south of those glacial bands, and in fact be the most equatorial of all. Based on the all the research I’ve reviewed on Martian glaciers, this shouldn’t glacial.
One clue that it was not glacial was the erosion pattern, with the highest feature at the crater’s center and the terraces descending concentrically outward to the crater’s rim. The glacial craters at higher latitude tended to be more flat, and seemed to instead descend toward the crater’s center.
The caption however did not say one way or the other. Moreover, it has been written back in 2007, before scientists had known much about the glacial features on Mars. If this was glacial it would be a big deal, as it was at the equator. I emailed Colin Dundas U.S. Geological Survey’s Astrogeology Science Center in Arizona, who wrote the caption and has been helpful previously. He confirmed the non-glacial nature of this crater.
That’s a different feature–it’s a set of rocky layers that lined the inside of an impact crater and were then planed off by erosion, producing a series of concentric rings. It’s distinct from the classic “concentric crater fill” that is due to ice creep and flow.
He also mentioned that there have been published reports of other equatorial craters that were ice-rich. I have located two stories suggesting the existence of glaciers close to the Martian equator.
- ‘Pack ice’ suggests frozen sea on Mars
- Analysis Sharpens Mars Hydrogen Map, Hinting Equatorial Water Ice
In both stories the presence of ice is only indirectly inferred. There is no direct evidence of water. This does not eliminate the possibility of equatorial Martian ice, but the science here remains very uncertain.
Meanwhile, the image above with its wedding cake mesa in the center of a crater remains quite fascinating. Assuming that the fill in the crater was once flat, and then eroded away to leave behind that central mesa, why has this erosion formed this concentric pattern? The theories mentioned in the caption are not very clear on this point. To repeat, the science is very uncertain.
The Martian landscape continues to amaze.
The support of my readers through the years has given 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. Four years ago, just before the 2020 election I wrote that Joe Biden's mental health was suspect. Only in this year has the propaganda mainstream media decided to recognize that basic fact.
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. Even today NASA and Congress refuse to 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.
Please consider supporting my work here at Behind the Black.
You can support me either by giving a one-time contribution or a regular subscription. There are five 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:
5. 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. And if you buy the books through the ebookit links, I get a larger cut and I get it sooner.
Looks like the flush-cut stump of some gigantic tree.