The wind-swept volcanic ash plains of Mars
Cool image time! In Mars’ volcano country lies the planet’s largest ash deposit, dubbed the Medusae Fossae Formation. Scientists believe that this gigantic deposit, with a size comparable to the nation of India, was laid down by muliple volcanic eruptions over several billion years and is the source of most of the dust seen on the Red Planet.
The overview map on the right shows the location of this ash deposit on Mars. The white cross indicates the location of today’s cool image, found below.
Click for full image.
The photo to the right, rotated, cropped, and enhanced to bring out the details, provides us a nice example of that ash deposit. Taken on May 10, 2021 by the high resolution camera on Mars Reconnaissance Orbiter (MRO), it shows how the prevailing southeast-to-northwest winds, weak as they are in the extremely thin Martian atmosphere, have in several billion years carved that ash deposit into a magnificent linear carpet.
Notice how the linear grooves remain aligned from terrace to terrace. Notice also how there is little dust or grooves at the cliff edges. This is especially pronounced in the full image, which also includes several areas where the grooves are less distinct as well as some smaller places where ridges are aligned at right angles.
This location, shown in the wider MRO context camera image below, is at the edge of a meandering gully suggestive of some sort of flow, usually assumed caused by liquid water but also by maybe water ice. The white box marks the area covered by the photo above.
The small many grooves at this spot also suggest that the ash deposit is somewhat thin. Compare it for example with the much larger grooves found near the deposit’s northern edge, about six hundred miles away. The difference suggests that the ash has been piling up to the north over time.
Only one other high resolution image has been taken by MRO near this location. Several miles to the south west, it only shows these linear grooves in its northeast quadant, suggesting it covers the edge of the ash deposit and reinforcing the impression that the ash is is very thin in the cool image above.
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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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Cool image time! In Mars’ volcano country lies the planet’s largest ash deposit, dubbed the Medusae Fossae Formation. Scientists believe that this gigantic deposit, with a size comparable to the nation of India, was laid down by muliple volcanic eruptions over several billion years and is the source of most of the dust seen on the Red Planet.
The overview map on the right shows the location of this ash deposit on Mars. The white cross indicates the location of today’s cool image, found below.
Click for full image.
The photo to the right, rotated, cropped, and enhanced to bring out the details, provides us a nice example of that ash deposit. Taken on May 10, 2021 by the high resolution camera on Mars Reconnaissance Orbiter (MRO), it shows how the prevailing southeast-to-northwest winds, weak as they are in the extremely thin Martian atmosphere, have in several billion years carved that ash deposit into a magnificent linear carpet.
Notice how the linear grooves remain aligned from terrace to terrace. Notice also how there is little dust or grooves at the cliff edges. This is especially pronounced in the full image, which also includes several areas where the grooves are less distinct as well as some smaller places where ridges are aligned at right angles.
This location, shown in the wider MRO context camera image below, is at the edge of a meandering gully suggestive of some sort of flow, usually assumed caused by liquid water but also by maybe water ice. The white box marks the area covered by the photo above.
The small many grooves at this spot also suggest that the ash deposit is somewhat thin. Compare it for example with the much larger grooves found near the deposit’s northern edge, about six hundred miles away. The difference suggests that the ash has been piling up to the north over time.
Only one other high resolution image has been taken by MRO near this location. Several miles to the south west, it only shows these linear grooves in its northeast quadant, suggesting it covers the edge of the ash deposit and reinforcing the impression that the ash is is very thin in the cool image above.
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.
Notice also the eddies surrounding a central hill in the full-size image. Suggests very uniform wind direction over the entire area. Heck of a place to get lost in . . .