Residual ice on the shaded north-facing slope of northern Martian crater
Click for original image.
Cool image time! The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on April 10, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). In the headline I am speculating a bit when I call that pile of material bunched up against the interior slope of this unnamed 18-mile-wide crater residual ice. No data is available to me that proves that assumption, but the look, the location, and the general previous data from Mars all tell me that this is what it is.
First, the location within the crater. Everyone who has lived in the northern latitudes where snow falls knows that snow will remain in the shaded slopes that face north — where less direct sunlight falls — much longer than in places where there is more sunlight. You can sometimes even find this residual snow as late as June and July in some such spots.
This phenomenon will be no different on Mars. In those alcoves this material, which looks exactly like glacial features found in many other places in the mid-latitudes of Mars (such as inside the small half-mile-wide crater in the lower left), is well protected, so that even when the rest of the ice sublimated away within the crater it remained. The cliff wall rises five hundred feet to the south, blocking sunlight so that for most of the year little directly sunlight touches this surface.
The red dot on the overview map marks the location of this crater. Located right at 30 degrees north latitude, it is not surprising that much of the near-surface ice here has sublimated away. So far scientists have identified very little evidence of glacial features south of this latitude. Instead, these equatorial latitudes comprise the dry regions of Mars.
In this crater however the ice in these north-facing alcoves has survived, as snow does in similar locations on Earth.
Note that we are probably looking at an early settlement location on Mars. There is near-surface ice at these latitudes, and only about 300 miles to the southwest are the long fissures called Nili Fossae, where orbital data has found evidence of a great deal of valuable minerals, thus making it ripe for mining (as shown in the upper right map at this August 2022 post).
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
Click for original image.
Cool image time! The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on April 10, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). In the headline I am speculating a bit when I call that pile of material bunched up against the interior slope of this unnamed 18-mile-wide crater residual ice. No data is available to me that proves that assumption, but the look, the location, and the general previous data from Mars all tell me that this is what it is.
First, the location within the crater. Everyone who has lived in the northern latitudes where snow falls knows that snow will remain in the shaded slopes that face north — where less direct sunlight falls — much longer than in places where there is more sunlight. You can sometimes even find this residual snow as late as June and July in some such spots.
This phenomenon will be no different on Mars. In those alcoves this material, which looks exactly like glacial features found in many other places in the mid-latitudes of Mars (such as inside the small half-mile-wide crater in the lower left), is well protected, so that even when the rest of the ice sublimated away within the crater it remained. The cliff wall rises five hundred feet to the south, blocking sunlight so that for most of the year little directly sunlight touches this surface.
The red dot on the overview map marks the location of this crater. Located right at 30 degrees north latitude, it is not surprising that much of the near-surface ice here has sublimated away. So far scientists have identified very little evidence of glacial features south of this latitude. Instead, these equatorial latitudes comprise the dry regions of Mars.
In this crater however the ice in these north-facing alcoves has survived, as snow does in similar locations on Earth.
Note that we are probably looking at an early settlement location on Mars. There is near-surface ice at these latitudes, and only about 300 miles to the southwest are the long fissures called Nili Fossae, where orbital data has found evidence of a great deal of valuable minerals, thus making it ripe for mining (as shown in the upper right map at this August 2022 post).
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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