Razor butte on Mars
Click for original image.
Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on November 18, 2022 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). The science team labeled this image “Inverted Channel and Possible Lake Deposits.” The sharp razor-like butte, which I estimate is about 200 to 400 feet high, is an example of the several inverted channels in the full image. The serrated-edged flat plateau at the top of this picture, one of several in the full image, is an example of those possible lake deposits.
Why do the scientists think a lake might have once been here? Located at 8 degrees north latitude in the dry equatorial regions of Mars, there is almost certainly no near surface ice here now.
As always, the overview map provides the context, and a possible explanation.
The dot west of Ganges canyon marks the location of this picture, which covers the northwest quadrant of a 30-mile-wide unnamed crater on the plateau north of the giant canyon Valles Marineris.
Scientists have accumulated a lot of evidence that the canyons and craters north of Valles Marineris once held lakes. For example, see this November 2020 post about a paper outlining the evidence that lakes and rivers once existed to the west of the sixty-mile-wide and three-mile deep Juventae Chasma, about 150 miles to the northwest of this crater. At that location MRO images found inverted channels similar to the razor butte above. As I wrote then,
What scientists think happened is that in the past an intermittent lake of varying depth … would come and go … at intervals separated by 100 to 100,000 years, with the lakes themselves possibly lasting as long at 10,000 years.
As the lakes ebbed and flowed, they eroded the bedrock on the floor of the crater. The ridges represent former flow channels. Because the channel floor was packed down by the flow, it became denser, and thus remained behind as the surrounding terrain was eroded away.
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.
Click for original image.
Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on November 18, 2022 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). The science team labeled this image “Inverted Channel and Possible Lake Deposits.” The sharp razor-like butte, which I estimate is about 200 to 400 feet high, is an example of the several inverted channels in the full image. The serrated-edged flat plateau at the top of this picture, one of several in the full image, is an example of those possible lake deposits.
Why do the scientists think a lake might have once been here? Located at 8 degrees north latitude in the dry equatorial regions of Mars, there is almost certainly no near surface ice here now.
As always, the overview map provides the context, and a possible explanation.
The dot west of Ganges canyon marks the location of this picture, which covers the northwest quadrant of a 30-mile-wide unnamed crater on the plateau north of the giant canyon Valles Marineris.
Scientists have accumulated a lot of evidence that the canyons and craters north of Valles Marineris once held lakes. For example, see this November 2020 post about a paper outlining the evidence that lakes and rivers once existed to the west of the sixty-mile-wide and three-mile deep Juventae Chasma, about 150 miles to the northwest of this crater. At that location MRO images found inverted channels similar to the razor butte above. As I wrote then,
What scientists think happened is that in the past an intermittent lake of varying depth … would come and go … at intervals separated by 100 to 100,000 years, with the lakes themselves possibly lasting as long at 10,000 years.
As the lakes ebbed and flowed, they eroded the bedrock on the floor of the crater. The ridges represent former flow channels. Because the channel floor was packed down by the flow, it became denser, and thus remained behind as the surrounding terrain was eroded away.
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.
Instapundit pointed to this piece (from Icarus last year) a handful of days ago, revealing evidence that there’s presently lots of water down under the floor of parts of Valles Marineris’ canyon(s), to wit: “The evidence for unusually high hydrogen abundances in the central part of Valles Marineris on Mars.” Don’t recall if you’d already talked about it….
Michael McNeil: Heh. Posted here on BtB in December 2021:
Scientists discover underground reservoir of hydrogen, likely ice, near Martian equator
What I do in my post that no one else in the press did was note the importance of the latitude. If confirmed as underground water ice, this would be a significant find, as it is in the dry equatorial regions of Mars.
… the dry equatorial regions of Mars.
Yes, that occurred to me too. Plus the floor of Valles Marineris is far lower than the surrounding dry plateau. It reminds me of something I heard about the Grand Canyon: Snow falls frequently at the Grand Canyon rim, but not a snowflake ever makes its way down (1 mile in elevation) to the bottom of the canyon. Yet at the bottom of (the even bigger) Valles Marineris on Mars – at a latitude otherwise quite dry – we appear to have found a great deal of “snow” (ice), that’s been maintaining itself there against sublimation for eons. Most fascinating!