Some new “What the heck?” geology on Mars
Click for original image.
Cool image time! The picture to the right, rotated, cropped, reduced, and enhanced to post here, was taken on April 21, 2024 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).
My first reaction on seeing this picture was to scratch my head? What am I looking at? Are those fluted dark features going downhill to the south, or uphill to the north? What are they? Are they slope streaks? Avalanches? How do they relate to the flat-topped ground in the middle of the picture?
I have made it easier for my readers to interpret the picture by adding the “low” and “high” markers. We are looking at two parallel thin mesas about 1,400 feet high, with the saddle between them only dropping about 350 feet.
But what about the dark fluted features? To understand what these are requires more information.
The white rectangle on the overview map to the right marks the location, in the very high latitudes (71 degrees south) of the Martian cratered highlands. The mesas are inside a complex depression dubbed Sisyphi Cavi.
Scientists have been using MRO since 2020 to monitor these mesas, because the light and dark areas appear to change drastically from Martian year to Martian year. The picture above was taken in the spring, yet it looks quite different from an earlier picture from 2020, also taken in the Martian spring. In that earlier picture the dark streaks are much smaller and the flat floor of the depression to the north is lighter, the stipples far less distinct.
At this high latitude, the ground almost certainly gets covered by the annual mantle of dry ice that falls as snow in the dark winter and then sublimates away with the coming of spring. It appears that process causes changes here. It also appears, from the label of this picture (“monitoring frost”) that orbital data has detected frost in these gullies. Both the frost and these seasonal changes could very well be what causes the gullies to erode away on the mesa slopes, with the visual changes indications of that process.
Readers!
My annual February birthday fund-raising drive for Behind the Black is now over. Thank you to everyone who donated or subscribed. While not a record-setter, the donations were more than sufficient and slightly above average.
As I have said many times before, I can’t express what it means to me to get such support, especially as no one is required to pay anything to read my work. Thank you all again!
For those readers who like my work here at Behind the Black and haven't contributed so far, please consider donating or subscribing. My analysis of space, politics, and culture, taken from the perspective of an historian, is almost always on the money and ahead of the game. For example, in 2020 I correctly predicted that the COVID 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. Every one of those 2020 conclusions has turned out right.
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.
Click for original image.
Cool image time! The picture to the right, rotated, cropped, reduced, and enhanced to post here, was taken on April 21, 2024 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).
My first reaction on seeing this picture was to scratch my head? What am I looking at? Are those fluted dark features going downhill to the south, or uphill to the north? What are they? Are they slope streaks? Avalanches? How do they relate to the flat-topped ground in the middle of the picture?
I have made it easier for my readers to interpret the picture by adding the “low” and “high” markers. We are looking at two parallel thin mesas about 1,400 feet high, with the saddle between them only dropping about 350 feet.
But what about the dark fluted features? To understand what these are requires more information.
The white rectangle on the overview map to the right marks the location, in the very high latitudes (71 degrees south) of the Martian cratered highlands. The mesas are inside a complex depression dubbed Sisyphi Cavi.
Scientists have been using MRO since 2020 to monitor these mesas, because the light and dark areas appear to change drastically from Martian year to Martian year. The picture above was taken in the spring, yet it looks quite different from an earlier picture from 2020, also taken in the Martian spring. In that earlier picture the dark streaks are much smaller and the flat floor of the depression to the north is lighter, the stipples far less distinct.
At this high latitude, the ground almost certainly gets covered by the annual mantle of dry ice that falls as snow in the dark winter and then sublimates away with the coming of spring. It appears that process causes changes here. It also appears, from the label of this picture (“monitoring frost”) that orbital data has detected frost in these gullies. Both the frost and these seasonal changes could very well be what causes the gullies to erode away on the mesa slopes, with the visual changes indications of that process.
Readers!
My annual February birthday fund-raising drive for Behind the Black is now over. Thank you to everyone who donated or subscribed. While not a record-setter, the donations were more than sufficient and slightly above average.
As I have said many times before, I can’t express what it means to me to get such support, especially as no one is required to pay anything to read my work. Thank you all again!
For those readers who like my work here at Behind the Black and haven't contributed so far, please consider donating or subscribing. My analysis of space, politics, and culture, taken from the perspective of an historian, is almost always on the money and ahead of the game. For example, in 2020 I correctly predicted that the COVID 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. Every one of those 2020 conclusions has turned out right.
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.
That is some concentrated weirdness right there!
A couple of good sized sand worms there.