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My July fund-raising campaign, celebrating the 13th anniversary of the start of this website, has now ended. This was the second most successful monthly fund-raising campaign ever. Thank you again to everyone who has who donated or subscribed. It is difficult to explain what your support means to me.


You can still donate or subscribe to support my work if you wish, 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.


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Eroding glacial ice on Mars, dipping in the wrong direction

Dipping wrongway ice terraces
Click for full image.

Today’s cool image is a variation of a similar phenomenon shown in a cool image I posted in July, dipping terraced layers stepping downhill toward a cliff face, rather than away from the cliff as you would expect. That previous example was located in chaos region in the northern mid-latitudes that I dub glacier country.

This example is instead found a completely different region of Mars, halfway across the planet. The photo to the right, cropped, reduced, and annotated to post here, was taken on March 1, 2022 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). The arrows indicate the downward trend of those dipping layers, toward the cliff face.

The overview map below provides the context.

Overview map

The black cross marks the location of the photo above. It is also in a land of glaciers, but this glacier country is to the east of Hellas Basin, in the southern cratered highlands, just to the west of the valley dubbed Reull Valles. I have posted a number of images taken of Reull Valles, all of which routinely show glacial features. In one image from August 2021 the entire canyon is filled from wall to wall with a flowing glacier, running downhill to Hellas.

The cliff face above is on the plateau above that canyon (as shown in this wider MRO context camera photo). While the canyon itself is filled with what clearly looks like a glacial flow, the plateau shows some evidence of glacial erosion, especially at the base of cliffs like the one above.

Genesis cover

On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.

The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.

The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.

"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News

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