Exploring the cratered southern highlands of Mars, part 3
Click for original image.
This is the third part of this week’s series taking a look at some of the strange features in the southern cratered highlands of Mars. In the first part I posted a beautiful image of what appears to be a crater filled to the brim with glacial ice, surrounded by an ice sheet plain. In part two we took a look at the interior of Rabe Crater, which though very nearby does not appear to have obvious glacial features within it at all. What it has instead are deep open air pits and a lot of sand dunes.
Today’s image to the right, cropped, reduced, and sharpened to post here, takes us to the interior of an unnamed 45-mile-wide crater only about 70 miles north of Rabe. The black dot in the inset on overview map above indicates the photo’s location. The picture was taken on January 1, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). Like Rabe, this crater also has many large open-air pits. In the picture one pit, near the lower center of the picture, is surrounded by soft-looking mounds and a strangely swirling textured and uneven terrain that makes up the majority of the crater’s floor.
This picture might help explain what we saw in Rabe. The textured terrain in this unnamed crater could easily be ice-impregnated and now hardened sand dunes. The pit could be where that impregnated ice has sublimated away, leaving behind the dust from those ancient dunes which then forms new sand dunes. In Rabe, the crater floor above its pits looks very similar to this swirling textured surface, suggesting the same process is going on there.
What strengthens this explanation is the many other craters nearby, all indicated by red dots in the overview map above, that also have pits or distorted crater floors. Their proximity suggests that there is an underground ice layer in this region, always at about the same elevation, and each crater impact exposed it. With time that exposed ice, no longer pure but filled with material from the impacts, sublimated partly away, producing the pits as well as ample sand to form sand dunes.
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.
This is the third part of this week’s series taking a look at some of the strange features in the southern cratered highlands of Mars. In the first part I posted a beautiful image of what appears to be a crater filled to the brim with glacial ice, surrounded by an ice sheet plain. In part two we took a look at the interior of Rabe Crater, which though very nearby does not appear to have obvious glacial features within it at all. What it has instead are deep open air pits and a lot of sand dunes.
Today’s image to the right, cropped, reduced, and sharpened to post here, takes us to the interior of an unnamed 45-mile-wide crater only about 70 miles north of Rabe. The black dot in the inset on overview map above indicates the photo’s location. The picture was taken on January 1, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). Like Rabe, this crater also has many large open-air pits. In the picture one pit, near the lower center of the picture, is surrounded by soft-looking mounds and a strangely swirling textured and uneven terrain that makes up the majority of the crater’s floor.
This picture might help explain what we saw in Rabe. The textured terrain in this unnamed crater could easily be ice-impregnated and now hardened sand dunes. The pit could be where that impregnated ice has sublimated away, leaving behind the dust from those ancient dunes which then forms new sand dunes. In Rabe, the crater floor above its pits looks very similar to this swirling textured surface, suggesting the same process is going on there.
What strengthens this explanation is the many other craters nearby, all indicated by red dots in the overview map above, that also have pits or distorted crater floors. Their proximity suggests that there is an underground ice layer in this region, always at about the same elevation, and each crater impact exposed it. With time that exposed ice, no longer pure but filled with material from the impacts, sublimated partly away, producing the pits as well as ample sand to form sand dunes.
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