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Readers!

 

The time has come for my annual short Thanksgiving/Christmas fund drive for Behind The Black. I must do this every year in order to make sure I have earned enough money to pay my bills.

 

For this two-week campaign, I am offering a special deal to encourage donations. Donations of $200 will get a free autographed copy of the new paperback edition of Genesis: The Story of Apollo 8, while donations of $250 will get a free autographed copy of the new hardback edition. If you desire a copy, make sure you provide me your address with your donation.

 

As I noted in July, 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. 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. Only now does it appear that Washington might finally 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.

 

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Hot spot in northern Martian crater?

Hot spot in northern Martian crater?
Click for full image.

Cool image time! The photo to the right, rotated, cropped, and reduced to post here, was taken on September 22, 2021 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows an unnamed four-mile-wide crater in the high northern lowland plains of Mars, at 60 degrees north latitude.

At 60 degrees latitude, it is likely that the crater’s interior is filled with buried glacial ice. A close look at the crater’s interior rim shows that whatever material fills the crater does not quite reach the rim. Furthermore, there are areas in the interior where it appears some slight sublimation has occurred. These features suggest the interior material is buried ice, but do not prove it.

What makes this crater intriguing however is the irregular depression at its center. When craters have a feature at the center, it usually is a central peak, caused at impact. The impact makes the ground act like a pond of water when you drop a pebble into it, with circular ripples (the crater rim) spreading outward and an uplift in the center (the central peak). In the case of a crater, the pond quickly freezes, locking those ripples and uplift in place.

Why a central depression then?

Wider context camera view
Click for full image.

The wider context MRO context camera image of the crater to the right might help explain this. Unlike most MRO photos, this image is an oblique one, looking sideways to the north. The splatter apron around the crater strengthens the hypothesis that there is a lot of near-surface ice at this high latitude, both inside, outside, and under the crater.

So why the central depression? My totally uneducated and very likely incorrect guess is that there is a hot spot spot where that central peak is located but buried under ice. The heat has caused the ice to sublimate away above, causing the depression.

Another possibility is that the depression reflects the topography of the ground below. Small craters like this usually do not have a central peak. Maybe when the impact happened there was further melt in the center, leaving a sinkhole?

All wild guesses. I really have no idea.

Note that the parallel east-west dark streaks in this context camera image are likely dust devil tracks, indicating the prevailing wind direction in this region.

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 print edition can be purchased at Amazon. from any other book seller, or direct from my ebook publisher, ebookit. 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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