Double-ringed crater near the Starship landing zone on Mars
Cool image time! The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on September 10, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows what the scientists label simply as a “double-rim crater.”
If you look close you might not be unreasonable to call this instead a triple-rim crater, as there appear to be two rings on each side of the highest crater rim.
Multple rings in craters are not rare. We see many on the Moon. Most however are associated with very large impacts, and are an expression of the ripples formed at impact, not unlike the ripples seen when you drop a pebble in water. Unlike water ripples, the ripples formed in rock are impact melt that quickly refreezes, thus capturing those ripples as concentric rings.
In this case, these rings likely signal not freezing rock but freezing ice.
The white cross on the overview map to the right marks this location, about 150 miles south of the Erebus Montes mountains and the prime landing sites for SpaceX’s Starship spaceship.
Orbital data has indicated that this region contains a lot of near surface ice, so much so that one scientist at a conference suggested you could hit ice simply by pushing a shovel into the ground almost anywhere. The crater’s rings as well as the star-shaped apron around it add weight to that data. This crater appears to have impacted ground heavily impregnated with ice, which allowed it to quickly melt and refreeze, leaving behind evidence of the ground’s motion during impact.
This entire region south of the Starship landing zone is very flat and relatively featureless, with few craters. Though flat, the ground itself has patterns that suggest an ice sheet. You can get a sense of this by looking at the original image.
All told, the evidence suggests that when those first humans land here they will not have to go far to find water.
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 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
Cool image time! The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on September 10, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows what the scientists label simply as a “double-rim crater.”
If you look close you might not be unreasonable to call this instead a triple-rim crater, as there appear to be two rings on each side of the highest crater rim.
Multple rings in craters are not rare. We see many on the Moon. Most however are associated with very large impacts, and are an expression of the ripples formed at impact, not unlike the ripples seen when you drop a pebble in water. Unlike water ripples, the ripples formed in rock are impact melt that quickly refreezes, thus capturing those ripples as concentric rings.
In this case, these rings likely signal not freezing rock but freezing ice.
The white cross on the overview map to the right marks this location, about 150 miles south of the Erebus Montes mountains and the prime landing sites for SpaceX’s Starship spaceship.
Orbital data has indicated that this region contains a lot of near surface ice, so much so that one scientist at a conference suggested you could hit ice simply by pushing a shovel into the ground almost anywhere. The crater’s rings as well as the star-shaped apron around it add weight to that data. This crater appears to have impacted ground heavily impregnated with ice, which allowed it to quickly melt and refreeze, leaving behind evidence of the ground’s motion during impact.
This entire region south of the Starship landing zone is very flat and relatively featureless, with few craters. Though flat, the ground itself has patterns that suggest an ice sheet. You can get a sense of this by looking at the original image.
All told, the evidence suggests that when those first humans land here they will not have to go far to find water.
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 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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