Patches of volcanic Martian ash covering patches of frozen volcanic dunes
Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on December 24, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).
What makes this terrain intriguing are the series of parallel ridges that cover most of the picture, with smaller ridges at right angles filling the hollows between. It appears we are looking at two different sets of dunes, the larger ridges indicating the southeast-to-northwest direction of the prevailing winds, while the smaller ridges in the hollows suggest the wind patterns within the hollows, causing smaller ripple dunes to form at right angles.
Note however the flat patches in the lower left. The material there appears to fill the hollows, covering the dunes. We can tell this by the hollows to the east, which have an almost identical dune pattern. Those flat patches then are likely covering similar dunes, with the patched material either having been blown away to expose the lower dunes, or having been blown here to cover them in patches. That the dunes appear unchanged under this patched material when exposed also suggests strongly that these dunes are hardened into stone, no longer soft sand that can be blown by the wind.
The white dot on the overview map to the right marks the location, on the edge of the Medusae Fossae Formation, the largest volcanic ash field on Mars. In the inset you can see that in this region the ash field is very patchy in general. The higher plateaus generally mark places where it is thick, with the lower areas in-between either exposed bedrock with little or no ash or ash in much thinner layers.
The picture above however tells us a lot about the creation of this vast volcanic ash field. It wasn’t placed here by one event, but by many individual events over long eons, with lots of time in-between to allow the formation and then hardening of those dunes into stone.
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.
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Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on December 24, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).
What makes this terrain intriguing are the series of parallel ridges that cover most of the picture, with smaller ridges at right angles filling the hollows between. It appears we are looking at two different sets of dunes, the larger ridges indicating the southeast-to-northwest direction of the prevailing winds, while the smaller ridges in the hollows suggest the wind patterns within the hollows, causing smaller ripple dunes to form at right angles.
Note however the flat patches in the lower left. The material there appears to fill the hollows, covering the dunes. We can tell this by the hollows to the east, which have an almost identical dune pattern. Those flat patches then are likely covering similar dunes, with the patched material either having been blown away to expose the lower dunes, or having been blown here to cover them in patches. That the dunes appear unchanged under this patched material when exposed also suggests strongly that these dunes are hardened into stone, no longer soft sand that can be blown by the wind.
The white dot on the overview map to the right marks the location, on the edge of the Medusae Fossae Formation, the largest volcanic ash field on Mars. In the inset you can see that in this region the ash field is very patchy in general. The higher plateaus generally mark places where it is thick, with the lower areas in-between either exposed bedrock with little or no ash or ash in much thinner layers.
The picture above however tells us a lot about the creation of this vast volcanic ash field. It wasn’t placed here by one event, but by many individual events over long eons, with lots of time in-between to allow the formation and then hardening of those dunes into stone.
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.
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