Strange glacial flow features on Mars?
Click for full image.
Cool image time! The photo to the right, rotated, cropped, and reduced to post here, was taken by the high resolution camera on Mars Reconnaissance Orbiter (MRO) on May 26, 2020, and shows what the scientists dub “Flow features in Reull Vallis.”
These features are typical in the mid-latitudes, and once again suggest the presence of buried glacial ice. The two lobes on the left and right both evoke such flows, as does the material in the drainage channel near the top of the photo.
What is more intriguing however are the strange features in the box. Below is that section, at full resolution.
The aligned ridges are quite interesting. Even more baffling are the ridges that get more pointed as they go downhill. This is completely the opposite what is usually seen, and is clearly seen in the two large lobes in the first image above. While the foot of a Martian glacial flow is not necessarily wider than its head, it generally is rounded like a lobe, which is why scientists dub them lobate.
For it to thin to a point as it goes down is puzzling. My guess is that we are seeing some evidence of erosion, or sublimation of that glacial material.
These flows are coming down off a mountain on the north wall of the downstream end of Reull Vallis, a 950 miles long and major meandering canyon in the Martian southern cratered highlands that drains into Hellas Basin, the death valley of Mars.
The overview map to the right provides the location context. Today’s image is indicated by the red cross. The black cross indicates the location of a previous cool image about Reull Vallis, which according to some scientists must have been formed by flowing water, as in a river. Based on more recent data and the accumulating evidence of extensive glacial activity in the Martian mid-latitudes, that conclusion is being challenged. Instead, it might be that such river-like meandering canyons might be the result of glacial flow over many eons.
The strange pointed ridges seen in today’s image might be evidence of the past cycles of glacial ebb and flow. Right now it is generally believed that the water ice is in steady-state between the poles and the mid-latitudes. At other times however that water either sublimated from the poles to the mid-latitudes, causing these glaciers to grow, or returned to the poles, causing these glaciers to shrink. The sharp ridges might indicate that shrink process.
Or not. I am guessing, based on my limited geological knowledge of Mars.
Now available in hardback and paperback as well as ebook!
From the press release: In this ground-breaking new history of early America, historian Robert Zimmerman not only exposes the lie behind The New York Times 1619 Project that falsely claims slavery is central to the history of the United States, he also provides profound lessons about the nature of human societies, lessons important for Americans today as well as for all future settlers on Mars and elsewhere in space.
Conscious Choice: The origins of slavery in America and why it matters today and for our future in outer space, is a riveting page-turning story that documents how slavery slowly became pervasive in the southern British colonies of North America, colonies founded by a people and culture that not only did not allow slavery but in every way were hostile to the practice.
Conscious Choice does more however. In telling the tragic history of the Virginia colony and the rise of slavery there, Zimmerman lays out the proper path for creating healthy societies in places like the Moon and Mars.
“Zimmerman’s ground-breaking history provides every future generation the basic framework for establishing new societies on other worlds. We would be wise to heed what he says.” —Robert Zubrin, founder of founder of the Mars Society.
All editions are available at Amazon, Barnes & Noble, and all book vendors, with the ebook priced at $5.99 before discount. The ebook can also be purchased direct from my ebook publisher, ebookit, in which case you don't support the big tech companies and I get a bigger cut much sooner.
Autographed printed copies are also available at discount directly from me (hardback $24.95; paperback $14.95; Shipping cost for either: $5.00). Just email me at zimmerman @ nasw dot org.
Click for full image.
Cool image time! The photo to the right, rotated, cropped, and reduced to post here, was taken by the high resolution camera on Mars Reconnaissance Orbiter (MRO) on May 26, 2020, and shows what the scientists dub “Flow features in Reull Vallis.”
These features are typical in the mid-latitudes, and once again suggest the presence of buried glacial ice. The two lobes on the left and right both evoke such flows, as does the material in the drainage channel near the top of the photo.
What is more intriguing however are the strange features in the box. Below is that section, at full resolution.
The aligned ridges are quite interesting. Even more baffling are the ridges that get more pointed as they go downhill. This is completely the opposite what is usually seen, and is clearly seen in the two large lobes in the first image above. While the foot of a Martian glacial flow is not necessarily wider than its head, it generally is rounded like a lobe, which is why scientists dub them lobate.
For it to thin to a point as it goes down is puzzling. My guess is that we are seeing some evidence of erosion, or sublimation of that glacial material.
These flows are coming down off a mountain on the north wall of the downstream end of Reull Vallis, a 950 miles long and major meandering canyon in the Martian southern cratered highlands that drains into Hellas Basin, the death valley of Mars.
The overview map to the right provides the location context. Today’s image is indicated by the red cross. The black cross indicates the location of a previous cool image about Reull Vallis, which according to some scientists must have been formed by flowing water, as in a river. Based on more recent data and the accumulating evidence of extensive glacial activity in the Martian mid-latitudes, that conclusion is being challenged. Instead, it might be that such river-like meandering canyons might be the result of glacial flow over many eons.
The strange pointed ridges seen in today’s image might be evidence of the past cycles of glacial ebb and flow. Right now it is generally believed that the water ice is in steady-state between the poles and the mid-latitudes. At other times however that water either sublimated from the poles to the mid-latitudes, causing these glaciers to grow, or returned to the poles, causing these glaciers to shrink. The sharp ridges might indicate that shrink process.
Or not. I am guessing, based on my limited geological knowledge of Mars.
Now available in hardback and paperback as well as ebook!
From the press release: In this ground-breaking new history of early America, historian Robert Zimmerman not only exposes the lie behind The New York Times 1619 Project that falsely claims slavery is central to the history of the United States, he also provides profound lessons about the nature of human societies, lessons important for Americans today as well as for all future settlers on Mars and elsewhere in space.
Conscious Choice: The origins of slavery in America and why it matters today and for our future in outer space, is a riveting page-turning story that documents how slavery slowly became pervasive in the southern British colonies of North America, colonies founded by a people and culture that not only did not allow slavery but in every way were hostile to the practice.
Conscious Choice does more however. In telling the tragic history of the Virginia colony and the rise of slavery there, Zimmerman lays out the proper path for creating healthy societies in places like the Moon and Mars.
“Zimmerman’s ground-breaking history provides every future generation the basic framework for establishing new societies on other worlds. We would be wise to heed what he says.” —Robert Zubrin, founder of founder of the Mars Society.
All editions are available at Amazon, Barnes & Noble, and all book vendors, with the ebook priced at $5.99 before discount. The ebook can also be purchased direct from my ebook publisher, ebookit, in which case you don't support the big tech companies and I get a bigger cut much sooner.
Autographed printed copies are also available at discount directly from me (hardback $24.95; paperback $14.95; Shipping cost for either: $5.00). Just email me at zimmerman @ nasw dot org.
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