Scroll down to read this post.


My February birthday fund-raising campaign for Behind the Black it now over. I sincerely and with deep gratitude thank all those who donated. Without your support I could not keep doing this, not so much because of the need for income to pay the bills, but because it tells me that there are people out there who want me to do this work. For those who did not contribute during the campaign, please consider adding your vote of support to Behind the Black, by giving either a one-time contribution or a regular subscription, in any one of the following ways:


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. Donate through Gabpay, using my email address zimmerman @ nasw dot org.

3. Patreon: Go to my website there and pick one of five monthly subscription amounts, or by making a one-time donation.

4. A Paypal Donation:

4. A Paypal subscription:

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

Mars’ polar ice canyons are young and the source for mid-latitude ice

Mars' north pole icecap
Mars’ north polar ice cap.

Scientists have now proposed that the giant ice canyons seen at the edges of Mars’ polar ice caps are very young and are also the source of the water that sublimates away when the planet’s rotational tilt (its obliquity) is high, to fall as snow in the mid-latitudes where it forms the glaciers and ice sheets we now find there.

The image to the right, reduced to post here, shows the entire north pole ice cape on the left, with its spiral canyons. The two inserts on the bottom show for scale Hawaii’s Big Island and the Grand Canyon. From the release:

“Erosion formed a huge ice canyon system, and that erosion is a source of the long-known mid-latitude mantles on Mars,” said Rodriguez, lead author of “North polar trough formation due to in‑situ erosion as a source of young ice in mid‑latitudinal mantles on Mars” that appears in Nature Scientific Reports.

The troughs are arranged in a vast spiral pattern covering an area the size of Texas. We find that their growth lateral to katabatic wind (wind that carries high-density colder air from a higher elevation down a slope) directions produced widespread simple intersections, from which the highly complex spiral arrangement emerged, Rodriguez said. “The spiral pattern seen in the troughs is basically an erosional byproduct,” he said. “As the pits grow and intersect over a pre-existing dome-shaped polar cap, the spiral pattern emerges.

“It has long been proposed that sublimation of water ice from the north polar cap during high-obliquity cycles was an essential source of the planet’s mid-latitude icy plains. Our finding identifies the troughs as direct evidence of those sublimation phases,” Rodriguez said.

These spiral trough features formed very recently, in geologic terms: between a few million and 50,000 years ago, Rodriguez said.

This hypothesis, if true, is very important in understanding the long term geological history of Mars. The present theory is that when the obliquity rises to as high of 60 degrees, compared to today’s 25 degrees (similar to Earth’s), the mid-latitudes are colder than the poles, and the ice at the poles then migrates to the mid-latitudes. This paper gives us the place at the poles where the icecap shrinks as that ice sublimates away.

Knowing that these polar canyons are young and the source of the mid-latitude ice scientists can now begin to write the geological history of the polar ice caps themselves. They can also use this information to maybe determine whether the caps are presently in a steady state, as now believed, or growing or shrinking.

The youth of these canyons also suggests that any mid-latitude ice from them is also young, and thus more likely pure water unpoisoned by the toxic perchlorates found in many places on the Martian surface. It will thus be easier to obtain pure drinkable water from them.

Conscious Choice cover

Now available in hardback and paperback as well as ebook!


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.


All editions are available at Amazon, Barnes & Noble, and all book vendors, with the ebook priced at $5.99 before discount. The ebook can also be purchased direct from my ebook publisher, ebookit, in which case you don't support the big tech companies and I get a bigger cut much sooner.


Autographed printed copies are also available at discount directly from me (hardback $24.95; paperback $14.95; Shipping cost for either: $5.00). Just email me at zimmerman @ nasw dot org.

Readers: the rules for commenting!


No registration is required. I welcome all opinions, even those that strongly criticize my commentary.


However, name-calling and obscenities will not be tolerated. First time offenders who are new to the site will be warned. Second time offenders or first time offenders who have been here awhile will be suspended for a week. After that, I will ban you. Period.


Note also that first time commenters as well as any comment with more than one link will be placed in moderation for my approval. Be patient, I will get to it.

Leave a Reply

Your email address will not be published. Required fields are marked *