High ridge down the center of a big Martian crack
Click for original image.
Cool image time! The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on January 27, 2025 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). Labeled simply as a “terrain sample,” it was likely taken not as part of any specific research project but to fill a gap in the schedule in order to maintain the camera’s proper temperature.
Whenever the camera team needs to do this, they try to find an interesting object to photograph, and often succeed. In this case they focused on the geology to the right. I suspect that at first glance my readers will have trouble deciphering what they are looking at. Let me elucidate: This this a 2.5-mile-wide canyon, about 1,000 feet deep, that is bisected by a ridge about 500 feet high.
On the sunlight walls of this canyon you can see boulders and debris, with material gathered on the canyon floor. The smoothness of the floor suggests also that a lot of Martian dust, likely volcanic ash, has become trapped there over the eons.
The white dot on the overview map to the right marks the location, in the cratered southern highlands of Mars but also within its dry equatorial regions.
The inset provides a very oblique view, looking north, with the white rectangle marking the approximate area covered by the photograph above. This canyon is actually part of a long series of parallel cracks that emanate outward to the southwest from the Tharsis Bulge where Mars’ largest volcanoes reside. These cracks are caused when pressure from below pushes upward and spreads the surface, cracking it.
In this particular spot however the ground separated in an unusual manner. It appears the crack wanted to shift its spread slightly to the south, and in doing so it caused two cracks, about fourteen-miles-long, with the ridge in the middle.
The ancientness of this crack is indicated by the thick dust on its floor, likely coming from the volcanic ash of the Medusae Fossae Formation. It took a long time for this ash to pile up inside the crack.
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 January 27, 2025 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). Labeled simply as a “terrain sample,” it was likely taken not as part of any specific research project but to fill a gap in the schedule in order to maintain the camera’s proper temperature.
Whenever the camera team needs to do this, they try to find an interesting object to photograph, and often succeed. In this case they focused on the geology to the right. I suspect that at first glance my readers will have trouble deciphering what they are looking at. Let me elucidate: This this a 2.5-mile-wide canyon, about 1,000 feet deep, that is bisected by a ridge about 500 feet high.
On the sunlight walls of this canyon you can see boulders and debris, with material gathered on the canyon floor. The smoothness of the floor suggests also that a lot of Martian dust, likely volcanic ash, has become trapped there over the eons.
The white dot on the overview map to the right marks the location, in the cratered southern highlands of Mars but also within its dry equatorial regions.
The inset provides a very oblique view, looking north, with the white rectangle marking the approximate area covered by the photograph above. This canyon is actually part of a long series of parallel cracks that emanate outward to the southwest from the Tharsis Bulge where Mars’ largest volcanoes reside. These cracks are caused when pressure from below pushes upward and spreads the surface, cracking it.
In this particular spot however the ground separated in an unusual manner. It appears the crack wanted to shift its spread slightly to the south, and in doing so it caused two cracks, about fourteen-miles-long, with the ridge in the middle.
The ancientness of this crack is indicated by the thick dust on its floor, likely coming from the volcanic ash of the Medusae Fossae Formation. It took a long time for this ash to pile up inside the crack.
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
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