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?
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.
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 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?
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.
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 was taken on my 55th birthday.
Looking at the oblique photo, and with the amount of ice likely present, my first impression was ‘Sploosh!’
Jeff-
very cool! (it was a simpler time, eh?!)
Blair–
Hunga Tonga volcano eruption
January 15, 2022
https://youtu.be/v_9FZLwlxTw
1:02
Wayne: Holy Shmazackral! Thanks, and another demonstration of the power of the natural world.
‘You want to see some climate change? Check this out!’ Every large volcano, ever.
My wife snickered at this. Not sure why.
I think you are spot on Bob. The small craters surrounding this all seem very deep and have no evidence of ejecta.
Even if the reason is not buried ice, the ground here is very unusual.
A great find!
Actually, I take back my previous statement regarding ejecta…. Just over halfway “north” on the bigger picture, “splat” ……
Sippin-Bourbon – My inner 14 rear old male was laughing when I saw this