A lunar crater wall two miles high
Cool image time! Considering this week is the 50th anniversary of the Apollo 11 lunar landing, it seems appropriate to show some cool images from the Moon.
Today the Lunar Reconnaissance Orbiter (LRO) science team released a spectacular oblique image of Giordano Bruno crater. The image on the right is cropped and very significantly reduced to post here. It looks across the crater, with the near rim across the bottom of the picture and the wall of the far rim filling the photograph’s top half.
That wall is what makes this image cool. It is a cliff about 10,000 feet high, equaling almost two miles. Moreover, at its base is a now-solidified melt pool left over from the impact that made the crater.
Faster than a speeding bullet – or rather ten times faster than a speeding bullet – is a good starting point in terms of grasping the energy released in a typical impact event. That is, for a bullet approaching 2 kilometers in diameter! The pressure and heat that were released during the collision not only excavated a hole much larger than the impactor but also melted a tremendous amount the target rock. Melt was sprayed and sloshed on the forming crater walls where much of it flowed back, seeking the lowest point in the impact crater. From the LROC vantage point you can follow the path taken by impact melt as it flowed across the irregular floor, ponding in closed depressions, and some of it ultimately reaching the lowest point.
Below the fold is a much higher resolution section of this photograph, focused on the crater wall and the melt pool. I have still been forced to reduce the resolution somewhat to post it here. Along that cliff wall can be seen partial avalanches (the dark splotch near the center) as well boulder tracks with the boulders (probably larger than most houses) still visible as white spots at the wall’s base.
The scale here is difficult to imagine. This cliff wall is three times as high as The Abyss, the steepest single drop viewpoint along the south rim of the Grand Canyon.
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.
You can support me either by giving a one-time contribution or a regular subscription. There are four ways of doing so:
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4. Donate by check, payable to Robert Zimmerman and mailed to
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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.
Cool image time! Considering this week is the 50th anniversary of the Apollo 11 lunar landing, it seems appropriate to show some cool images from the Moon.
Today the Lunar Reconnaissance Orbiter (LRO) science team released a spectacular oblique image of Giordano Bruno crater. The image on the right is cropped and very significantly reduced to post here. It looks across the crater, with the near rim across the bottom of the picture and the wall of the far rim filling the photograph’s top half.
That wall is what makes this image cool. It is a cliff about 10,000 feet high, equaling almost two miles. Moreover, at its base is a now-solidified melt pool left over from the impact that made the crater.
Faster than a speeding bullet – or rather ten times faster than a speeding bullet – is a good starting point in terms of grasping the energy released in a typical impact event. That is, for a bullet approaching 2 kilometers in diameter! The pressure and heat that were released during the collision not only excavated a hole much larger than the impactor but also melted a tremendous amount the target rock. Melt was sprayed and sloshed on the forming crater walls where much of it flowed back, seeking the lowest point in the impact crater. From the LROC vantage point you can follow the path taken by impact melt as it flowed across the irregular floor, ponding in closed depressions, and some of it ultimately reaching the lowest point.
Below the fold is a much higher resolution section of this photograph, focused on the crater wall and the melt pool. I have still been forced to reduce the resolution somewhat to post it here. Along that cliff wall can be seen partial avalanches (the dark splotch near the center) as well boulder tracks with the boulders (probably larger than most houses) still visible as white spots at the wall’s base.
The scale here is difficult to imagine. This cliff wall is three times as high as The Abyss, the steepest single drop viewpoint along the south rim of the Grand Canyon.
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.
This reminds me of the stats for the earth. If the earth was round (no bumps “mountains”) the water would be nearly 2 miles deep. My Everest is nearly thrice this above sea level.
The outstanding aspect here is that this 10,000ft relief was caused by an impact.
WOW
What is really amazing is how quickly these craters are excavated! Even that largest impacts are ‘over’ in a few minutes…
https://www.lpi.usra.edu/exploration/training/resources/impact_cratering/