Flow channels on Mars
Click for original image.
Cool image time! The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on May 13, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows what the scientists call a “channel and depression”, though to my eye everything looks like flow channels, descending to the east.
The drop from the narrow northern channel to wider southern channel is about 200 feet, with the small crater on the left sitting about halfway between. To our Earthbound eyes, something clearly flowed downhill from that northern channel into the wider channel. What we don’t know now is what the material was that did the flowing?
Was it liquid water? Glaciers? The overview map below provides some context, though it doesn’t actually provide an answer.
The red dot north of Kasei Valles on the overflow map to the right marks this location. The black in Kasei Valles is an ancient lava flow thought to have followed the older channel. The blue area marks a hypothesized lake formed by an ice dam (the white line).
The channels in the picture above were formed in a region where there are many similar flow features, all descending to the east and draining into Chryse Planitia in the northern lowland plains of Mars. While the consensus theory says that these channels were likely formed by catastrophic floods of liquid water, that theory remains unproven with many caveats, the most important of which is that no scientist has yet come up with a convincing model that would have ever allowed liquid water to exist on the surface of Mars.
It is possible that ice, flowing as a glacier, could have produced these channels. This location however is puzzling, in that despite being at 37 degrees north latitude, where orbital images normally detect many glacial features, few such features are visible. The only suggestion that there is near surface ice here is that craters all appear to be rimless, suggesting impacts into soft ice-impregnated soil.
The mystery remains however. These channels could have been formed from liquid or frozen water, but we simply do not have enough data to say which.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon or from any other book seller. If you want an autographed copy the price is $60 for the hardback and $45 for the paperback, plus $8 shipping for each. Go here for purchasing details. The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
Click for original image.
Cool image time! The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on May 13, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows what the scientists call a “channel and depression”, though to my eye everything looks like flow channels, descending to the east.
The drop from the narrow northern channel to wider southern channel is about 200 feet, with the small crater on the left sitting about halfway between. To our Earthbound eyes, something clearly flowed downhill from that northern channel into the wider channel. What we don’t know now is what the material was that did the flowing?
Was it liquid water? Glaciers? The overview map below provides some context, though it doesn’t actually provide an answer.
The red dot north of Kasei Valles on the overflow map to the right marks this location. The black in Kasei Valles is an ancient lava flow thought to have followed the older channel. The blue area marks a hypothesized lake formed by an ice dam (the white line).
The channels in the picture above were formed in a region where there are many similar flow features, all descending to the east and draining into Chryse Planitia in the northern lowland plains of Mars. While the consensus theory says that these channels were likely formed by catastrophic floods of liquid water, that theory remains unproven with many caveats, the most important of which is that no scientist has yet come up with a convincing model that would have ever allowed liquid water to exist on the surface of Mars.
It is possible that ice, flowing as a glacier, could have produced these channels. This location however is puzzling, in that despite being at 37 degrees north latitude, where orbital images normally detect many glacial features, few such features are visible. The only suggestion that there is near surface ice here is that craters all appear to be rimless, suggesting impacts into soft ice-impregnated soil.
The mystery remains however. These channels could have been formed from liquid or frozen water, but we simply do not have enough data to say which.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon or from any other book seller. If you want an autographed copy the price is $60 for the hardback and $45 for the paperback, plus $8 shipping for each. Go here for purchasing details. The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News