Springtime on Martian dunes near the north pole
Cool image time! The photo to the right, rotated and cropped to post here, was taken by the high resolution camera on Mars Reconnaissance Orbiter (MRO) on April 27, 2021. It shows a strange scattering of dunes on a flat plain. The red at the top of each dune probably indicates exposed dust and sand. The white fringe is likely either water frost or the leftover mantle of dry ice that is deposited in the polar regions each winter down to 60 degrees latitude, and disappears with the coming of spring, sublimating back into carbon dioxide gas.
There are a lot of puzzles here. The overview map below provides some context, but only some.
This location, marked by the black cross, is at 76 degrees north latitude, putting it only about 800 miles away from the north pole. It also sits in the vast sea of sand dunes that circles the north polar ice cap, in an area where dunes cover between 11% to 79% of the surface.
Why these dunes however should be so individual and scattered, with some aligned in a string, is not clear. Nor is it presently understood why the north polar icecap of Mars is surrounded by this ring of sand dunes, while the south polar icecap is not. There are dunes in the south, but no where as many or gathered for endless trackless distances.
Locations such as this are regularly monitored by scientists using MRO to see if the changing seasons cause any changes to the dunes. The coming and going of the dry ice mantle could cause small avalanches and erosion in the dunes.
At the same time, the coldness at this location and the presence of water ice in the ground means that changes are not easy. While these are sand dunes they are not made of loose flowing sand. It has been hardened, and will only break apart with significant stress.
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:
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Cool image time! The photo to the right, rotated and cropped to post here, was taken by the high resolution camera on Mars Reconnaissance Orbiter (MRO) on April 27, 2021. It shows a strange scattering of dunes on a flat plain. The red at the top of each dune probably indicates exposed dust and sand. The white fringe is likely either water frost or the leftover mantle of dry ice that is deposited in the polar regions each winter down to 60 degrees latitude, and disappears with the coming of spring, sublimating back into carbon dioxide gas.
There are a lot of puzzles here. The overview map below provides some context, but only some.
This location, marked by the black cross, is at 76 degrees north latitude, putting it only about 800 miles away from the north pole. It also sits in the vast sea of sand dunes that circles the north polar ice cap, in an area where dunes cover between 11% to 79% of the surface.
Why these dunes however should be so individual and scattered, with some aligned in a string, is not clear. Nor is it presently understood why the north polar icecap of Mars is surrounded by this ring of sand dunes, while the south polar icecap is not. There are dunes in the south, but no where as many or gathered for endless trackless distances.
Locations such as this are regularly monitored by scientists using MRO to see if the changing seasons cause any changes to the dunes. The coming and going of the dry ice mantle could cause small avalanches and erosion in the dunes.
At the same time, the coldness at this location and the presence of water ice in the ground means that changes are not easy. While these are sand dunes they are not made of loose flowing sand. It has been hardened, and will only break apart with significant stress.
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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