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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.


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:

4. A Paypal subscription:

5. Donate by check, payable to Robert Zimmerman and mailed to
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c/o Robert Zimmerman
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Confused glaciers in a Martian crater

Confused glaciers in a Martian crater
Click for original image.

Cool image time. The picture to the right, cropped to post here, was taken on February 2, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO), and shows a strangely blobby crater in the northern mid-latitudes where glacial features are frequently found inside craters.

In this case however the glacier seems very confused. As this is in the northern hemisphere, you would expect glacial material to survive on the north-facing southern interior slopes of the crater, where there is year-round less sunlight. The mottled eroded terrain in the south part of the crater floor suggests this. However, the crater also clearly has a terraced glacier on its south-facing northern interior slopes.

Why has the glacial material survived in both places, but not in the center of the crater?

In addition, there is that strange roughly circular feature attached to the south side of the crater. What formed it? Is it a glacier on the plains surrounding the crater? Or are we looking at volcanic material?

This crater is also unique. The crater just to its southwest (partly seen in the cropped image above), is a much more typical glacial-filled mid-latitude crater, its interior material more evenly distributed and its circular rim only slightly distorted.

Overview map

The white dot equidistant between the shield volcano Alba Mons and the rough fractured Tempe Terra region marks the location of this crater. It sits in a flattish plain surrounded by mountains and the fractured slopes rising upward towards the nearby giant volcanoes.

The location is at 46 degrees north latitude. Though it is in the mid-latitude band where many glaciers in craters are found, this is region where the glacier features are generally only found inside craters. Ice might be present underground, but its presence is not obvious.

Moreover, volcanic processes were a major component in creating this terrain. For all we know (which is not much), the strange feature on the south side of this crater and the mottled material inside the crater could very well be hardened flood lava that leaked from the crater itself.

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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