Where the Martian landscape begins to dry out
Click for original image.
Today’s cool image to the right, cropped, reduced, and sharpened to post here, provides us a glimpse at the lower mid-latitudes of Mars where the terrain is beginning to dry out as we move south. The picture was taken on April 29, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO), and shows what the scientists label “large linear features.”
The main north-south ridge is only about 20-25 feet high, and its meandering nature (which can be seen more clearly in the full image) suggests it is possibly an inverted channel, formed when the bed of a former canyon gets compressed by the water or ice that flows through it, and when the surrounding terrain gets eroded away that channel bed becomes a ridge.
These ridges however could also possibly be volcanic dikes, where magma had pushed up through fractures and faults to form these more resistant ridges.
On the overview map to the right the red dot in the inset marks the location, on the southern cratered highlands just south of the chaos terrain dubbed Nilosyrtis Mensae. Nilosyrtis forms the eastern end of the 2,000-mile-long northern mid-latitude strip I dub glacier country, because almost every image shows a surface covered with glacial features.
Today’s picture is located at 32 degrees north latitude, at the point where glacial features begin to disappear on Mars. As one travels south from here the ground becomes exposed, as it is this image, dry bedrock with no evidence of near surface ice. By the time you reach Perseverance in Jezero Crater at about 18 degrees north latitude you are in a dry, barren, but very cold desert.
The intriguing aspect of the ridges in this image is that they appear to be an example of chaos terrain, in reverse. The chaos terrain in glacier country is made up of mesas criss-crossed by straight canyons. Here, we have straight ridges criss-crossing lower terrain. The origin of both geologies are probably related, as the ridges and canyons likely mark the locations of fault lines. The mystery is why the difference. In the northern icy mensae region the material in those fault lines erodes away first. Here however it is more resistant.
Readers!
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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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Click for original image.
Today’s cool image to the right, cropped, reduced, and sharpened to post here, provides us a glimpse at the lower mid-latitudes of Mars where the terrain is beginning to dry out as we move south. The picture was taken on April 29, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO), and shows what the scientists label “large linear features.”
The main north-south ridge is only about 20-25 feet high, and its meandering nature (which can be seen more clearly in the full image) suggests it is possibly an inverted channel, formed when the bed of a former canyon gets compressed by the water or ice that flows through it, and when the surrounding terrain gets eroded away that channel bed becomes a ridge.
These ridges however could also possibly be volcanic dikes, where magma had pushed up through fractures and faults to form these more resistant ridges.
On the overview map to the right the red dot in the inset marks the location, on the southern cratered highlands just south of the chaos terrain dubbed Nilosyrtis Mensae. Nilosyrtis forms the eastern end of the 2,000-mile-long northern mid-latitude strip I dub glacier country, because almost every image shows a surface covered with glacial features.
Today’s picture is located at 32 degrees north latitude, at the point where glacial features begin to disappear on Mars. As one travels south from here the ground becomes exposed, as it is this image, dry bedrock with no evidence of near surface ice. By the time you reach Perseverance in Jezero Crater at about 18 degrees north latitude you are in a dry, barren, but very cold desert.
The intriguing aspect of the ridges in this image is that they appear to be an example of chaos terrain, in reverse. The chaos terrain in glacier country is made up of mesas criss-crossed by straight canyons. Here, we have straight ridges criss-crossing lower terrain. The origin of both geologies are probably related, as the ridges and canyons likely mark the locations of fault lines. The mystery is why the difference. In the northern icy mensae region the material in those fault lines erodes away first. Here however it is more resistant.
Readers!
Please consider supporting my work here at Behind the Black. Your support allows 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.
You can support me 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 or subscription:
4. Donate by check, payable to Robert Zimmerman and mailed to
Behind The Black
c/o Robert Zimmerman
P.O.Box 1262
Cortaro, AZ 85652
You can also support me by buying one of my books, as noted in the boxes interspersed throughout the webpage or shown in the menu above.
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