Giant dunes in a dune sea inside a Martian crater
Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on July 17, 2024 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).
The white dot on the overview map above marks the location, inside a thirty-mile-wide dune sea, or erg, that sits in the center of the floor of 80-mile-wide Russell Crater.
That erg is interesting in that it appears the dunes get larger and larger as you move from the perimeter to its center. Thus, the dunes in the picture are called mega-dunes, about 200-feet-high. They dwarf the smaller dunes at the erg’s edge.
This picture was taken as part of a long term monitoring program to track the coming and going of seasonal dry ice frost on these dunes. It is summer when this picture was taken, so there is relatively little visible frost, though the bright blue areas in the color strip could possibly be the last remnants from winter. In winter, data suggests the entire surface of these dunes is covered by dry ice frost.
As the location is at 54 degrees south latitude, it likely sits at the northernmost edge of the southern dry ice mantle that in winter covers each of the Martian poles, down to about 60 degrees latitude.
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 July 17, 2024 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).
The white dot on the overview map above marks the location, inside a thirty-mile-wide dune sea, or erg, that sits in the center of the floor of 80-mile-wide Russell Crater.
That erg is interesting in that it appears the dunes get larger and larger as you move from the perimeter to its center. Thus, the dunes in the picture are called mega-dunes, about 200-feet-high. They dwarf the smaller dunes at the erg’s edge.
This picture was taken as part of a long term monitoring program to track the coming and going of seasonal dry ice frost on these dunes. It is summer when this picture was taken, so there is relatively little visible frost, though the bright blue areas in the color strip could possibly be the last remnants from winter. In winter, data suggests the entire surface of these dunes is covered by dry ice frost.
As the location is at 54 degrees south latitude, it likely sits at the northernmost edge of the southern dry ice mantle that in winter covers each of the Martian poles, down to about 60 degrees latitude.
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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