Layered glaciers in Mars’ glacier country
Click for full image.
Cool image time. The photo to the right, cropped and reduced to post here, was taken on August 30, 2021 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows two different impact craters in a glacial region dubbed Nilosyrtis Mensae, located in the northern mid-latitudes in the 2,000 mile long strip chaos terrain that I have labeled glacier country because practically every image finds them there.
The splash apron surrounding the larger crater is typical of craters in Martian regions where ice is thought to be near the surface.
What makes this picture interesting is that the glaciers appear layered. You can see evidence of this in the mounds inside both craters. Those mounds appear to represent earlier periods when there was more ice here. Since then the mounds have partly sublimated away.
You can also see evidence of layers in the material surrounding the nearby larger mounds.
The map below shows us where this image is, relative to all of glacier country as well as the rover Perseverance in Jezero Crater.
The white cross marks the location of this image, at 41 degrees north latitude. Perseverance is a bit more than a thousand miles to the southeast, at about 18 degrees north latitude.
At this location, practically every image screams glaciers and ice. At Perseverance, only 23 degrees of latitude further south, the ground is dry.
Maybe the most interesting feature in this photo is the smaller crater. The impact appears to have drilled into the icy mounds, leaving a crater with no upraised rim on the high mound side, and no rim at all on the low side. Most intriguing.
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 full image.
Cool image time. The photo to the right, cropped and reduced to post here, was taken on August 30, 2021 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows two different impact craters in a glacial region dubbed Nilosyrtis Mensae, located in the northern mid-latitudes in the 2,000 mile long strip chaos terrain that I have labeled glacier country because practically every image finds them there.
The splash apron surrounding the larger crater is typical of craters in Martian regions where ice is thought to be near the surface.
What makes this picture interesting is that the glaciers appear layered. You can see evidence of this in the mounds inside both craters. Those mounds appear to represent earlier periods when there was more ice here. Since then the mounds have partly sublimated away.
You can also see evidence of layers in the material surrounding the nearby larger mounds.
The map below shows us where this image is, relative to all of glacier country as well as the rover Perseverance in Jezero Crater.
The white cross marks the location of this image, at 41 degrees north latitude. Perseverance is a bit more than a thousand miles to the southeast, at about 18 degrees north latitude.
At this location, practically every image screams glaciers and ice. At Perseverance, only 23 degrees of latitude further south, the ground is dry.
Maybe the most interesting feature in this photo is the smaller crater. The impact appears to have drilled into the icy mounds, leaving a crater with no upraised rim on the high mound side, and no rim at all on the low side. Most intriguing.
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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