Massive landslide in Martian canyon
Click for original image.
Cool image time! The picture to the right, cropped, reduced, enhanced, and annotated to post here, was taken on September 5, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).
The image shows a gigantic landslide collapse on the southern interior wall of a long meandering canyon on Mars dubbed Bahram Vallis. The collapse was what scientists call a mass wasting event, in which the entire section of cliff wall breaks off and moves downward as a large unit. In this case the falling section, a half mile wide and long, got squeezed near the bottom, piling up rather than flowing out into the canyon floor.
At this particular location the canyon is 2.4 miles wide, with cliff walls about 1,700 feet high. Imagine when this piece broke off: In one instance a giant section of mountain about a half mile long fell about a thousand feet. Even in Mars’ thin atmosphere the sound must have been thunderous.
The white dot in the inset on the overview map to the right indicates the location of this avalanche inside Bahram Vallis. The black areas inside Kasei Valles mark a past lava flow. The white line is a theorized ice dam that created a theorized lake as indicated in blue.
Though Bahram Vallis is one of the smaller such canyons on Mars, only slightly less than 200 miles long, it is remarkably distinct and well defined, with a width consistently between two and four miles along its entire length, thus making it look more like a lava rill than a river canyon. Though there are erosional features inside the canyon that suggest flowing liquid, its consistent and distinct meandering shape once again suggests that glaciers rather than flowing water might have carved it.
Scientists also believe these mass wasting events are linked somehow to the presence of underground water or ice impregnated in the ground that weakens it. If so, that water or ice is long gone at this location, as it is inside the dry equatorial regions of Mars, where orbital data has so far found no near surface ice. The remains of this avalanche are therefore very old, though an exact date cannot be determined based on the available data.
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. from any other book seller, or direct from my ebook publisher, ebookit.
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, cropped, reduced, enhanced, and annotated to post here, was taken on September 5, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).
The image shows a gigantic landslide collapse on the southern interior wall of a long meandering canyon on Mars dubbed Bahram Vallis. The collapse was what scientists call a mass wasting event, in which the entire section of cliff wall breaks off and moves downward as a large unit. In this case the falling section, a half mile wide and long, got squeezed near the bottom, piling up rather than flowing out into the canyon floor.
At this particular location the canyon is 2.4 miles wide, with cliff walls about 1,700 feet high. Imagine when this piece broke off: In one instance a giant section of mountain about a half mile long fell about a thousand feet. Even in Mars’ thin atmosphere the sound must have been thunderous.
The white dot in the inset on the overview map to the right indicates the location of this avalanche inside Bahram Vallis. The black areas inside Kasei Valles mark a past lava flow. The white line is a theorized ice dam that created a theorized lake as indicated in blue.
Though Bahram Vallis is one of the smaller such canyons on Mars, only slightly less than 200 miles long, it is remarkably distinct and well defined, with a width consistently between two and four miles along its entire length, thus making it look more like a lava rill than a river canyon. Though there are erosional features inside the canyon that suggest flowing liquid, its consistent and distinct meandering shape once again suggests that glaciers rather than flowing water might have carved it.
Scientists also believe these mass wasting events are linked somehow to the presence of underground water or ice impregnated in the ground that weakens it. If so, that water or ice is long gone at this location, as it is inside the dry equatorial regions of Mars, where orbital data has so far found no near surface ice. The remains of this avalanche are therefore very old, though an exact date cannot be determined based on the available data.
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. from any other book seller, or direct from my ebook publisher, ebookit. 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
Perhaps the mass slumped rapidly, rather than so much falling. 0.3g. I have seen video of landslides moving at little more than walking pace, but relentlessly so.