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I am now running my annual July fund-raising campaign to celebrate the twelfth anniversary of the establishment of Behind the Black. For many reasons, mostly political but partly ethical, I do not use Google, Facebook, Twitter. These companies practice corrupt business policies, while targeting conservative websites for censoring, facts repeatedly confirmed by news stories and by my sense that Facebook has taken action to prevent my readers from recommending Behind the Black to their friends.


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Mars: Glaciers on top of glaciers on top of glaciers

Overview map
Mars’ glacier country.

glaciers on top of glaciers on top of glaciers
Click for full image.

Cool image time! The photo to the right, rotated, cropped, and reduced to post here, was taken on December 12, 2021 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows a small patch of layered glacial features flowing in all directions. The overview map above marks its location by the red dot, at 40 degrees north latitude in the region dubbed Deuteronilus Mensae, on the western end of the 2,000 long strip from 30 to 60 degrees north latitude that I dub Mars’s glacier country because practically every image in this region shows glacial features.

What makes the glacial features in this picture so remarkable is their number, their somewhat chaotic nature, and the evidence of many layers, suggesting a cyclical process of ebb and flow over the eons.

Below I zoom into one section of this photo, showing that section at full resolution.

Close-up on layered glaciers

According to the most favored hypothesis attempting to explain much of Mars’ geology, the planet’s wide swings in its rotational tilt, from 11 to 60 degrees, cause cycles of glacial growth and erosion. When the tilt is low, the poles are colder than the mid-latitudes, and water migrates from glaciers in these mid-latitude bands to the icecaps at the poles, thus causing the glaciers to shrink. When the tilt is high, the mid-latitudes are colder than the poles, and that water migrates back from the polar icecaps so that the glaciers in these mid-latitude bands grow.

What the layers in the ice mesa on the right are suggesting however is that with each cycle, the glaciers grew less with each growth period. Each time the glaciers shrank, they grew back less, producing the wedding cake layered mesa we see here.

This also provides circumstantial evidence that the amount of water on Mars was shrinking steadily during these cycles. It is far from gone, but there is clearly less there now than existed in the far past.

Make sure you click on the full image. The number of weird features in this one MRO photo is quite amazing. They truly illustrate the alienness of the Martian landscape.

Conscious Choice cover

From the press release: In this ground-breaking new history of early America, historian Robert Zimmerman not only exposes the lie behind The New York Times 1619 Project that falsely claims slavery is central to the history of the United States, he also provides profound lessons about the nature of human societies, lessons important for Americans today as well as for all future settlers on Mars and elsewhere in space.

Conscious Choice: The origins of slavery in America and why it matters today and for our future in outer space, is a riveting page-turning story that documents how slavery slowly became pervasive in the southern British colonies of North America, colonies founded by a people and culture that not only did not allow slavery but in every way were hostile to the practice.  
Conscious Choice does more however. In telling the tragic history of the Virginia colony and the rise of slavery there, Zimmerman lays out the proper path for creating healthy societies in places like the Moon and Mars.


“Zimmerman’s ground-breaking history provides every future generation the basic framework for establishing new societies on other worlds. We would be wise to heed what he says.” —Robert Zubrin, founder of founder of the Mars Society.


Available everywhere for $3.99 (before discount) at Amazon, Barnes & Noble, and all ebook vendors, or direct from the ebook publisher, ebookit. And if you buy it from ebookit you don't support the big tech companies and I get a bigger cut much sooner.

One comment

  • Alex Andrite

    “The number of weird features in this one MRO photo is quite amazing. They truly illustrate the alienness of the Martian landscape.”

    Now a Martian landscape of so long ago, a massive battlefield, the vanquished remains now covered with the settled dust of death.
    No soil to bury them here, but dust., empty sterile dust.
    The decaying living spoils have been carried off long ago, yesterday.

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