Pedestal craters in the Martian northern lowlands?
Cool image time! The photo on the right, cropped and reduced to post here, shows a cluster of really strange mesas, craters, and pits, located in Utopia Planitia, the largest and deepest plain of Mars’ northern lowlands where an intermittent ocean might have once existed.
The image was taken on October 26, 2019 by the high resolution camera on Mars Reconnaissance Orbiter (MRO) as part of its regular image-taking program. In this case it was dubbed a “terrain sample” image, meaning that it was not specifically requested by any researcher, but was taken because they need to use the camera regularly to maintain its temperature, and thus sometime produce images over previously untouched areas, not knowing what they will find, as part of that maintenance schedule.
In this case the terrain sampled is especially intriguing. Are the upraised depressions what are called pedestal craters, created when the impact landed on what was once an icy plain, which subsequently sublimated away to leave the crater sitting high above the surrounding flats? Maybe, but this location is at 23 degrees north latitude, and research has generally found these pedestal craters at latitudes higher than 30 degrees.
Moreover, that many of these upraised depressions are not circular suggests that their formation was not impact related.
Other mysteries: Why are all the ridgelines bright? What caused the parallel white streaks to the east and west of some mesas? And if these are impact craters, why are some distorted?
If this region was once the seabed of an intermittent ocean, this fact might explain the features. Then again, it is more likely that this lowland area was once covered in ice in the far past, when the planet’s tilt was greater and the lower latitudes were actually colder than the polar regions, and thus allowed ice to build up in those lower latitudes. We might therefore be seeing the end result of an erosion/sublimation process as that ice disappeared when Mars’ inclination shifted.
Lots of questions, and no answers.
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. from any other book seller, or direct from my ebook publisher, ebookit.
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 photo on the right, cropped and reduced to post here, shows a cluster of really strange mesas, craters, and pits, located in Utopia Planitia, the largest and deepest plain of Mars’ northern lowlands where an intermittent ocean might have once existed.
The image was taken on October 26, 2019 by the high resolution camera on Mars Reconnaissance Orbiter (MRO) as part of its regular image-taking program. In this case it was dubbed a “terrain sample” image, meaning that it was not specifically requested by any researcher, but was taken because they need to use the camera regularly to maintain its temperature, and thus sometime produce images over previously untouched areas, not knowing what they will find, as part of that maintenance schedule.
In this case the terrain sampled is especially intriguing. Are the upraised depressions what are called pedestal craters, created when the impact landed on what was once an icy plain, which subsequently sublimated away to leave the crater sitting high above the surrounding flats? Maybe, but this location is at 23 degrees north latitude, and research has generally found these pedestal craters at latitudes higher than 30 degrees.
Moreover, that many of these upraised depressions are not circular suggests that their formation was not impact related.
Other mysteries: Why are all the ridgelines bright? What caused the parallel white streaks to the east and west of some mesas? And if these are impact craters, why are some distorted?
If this region was once the seabed of an intermittent ocean, this fact might explain the features. Then again, it is more likely that this lowland area was once covered in ice in the far past, when the planet’s tilt was greater and the lower latitudes were actually colder than the polar regions, and thus allowed ice to build up in those lower latitudes. We might therefore be seeing the end result of an erosion/sublimation process as that ice disappeared when Mars’ inclination shifted.
Lots of questions, and no answers.
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. from any other book seller, or direct from my ebook publisher, ebookit. 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
Hi Bob,
I have worked with Philip Stooke who is the author of the Lunar Atlas. We have identified the lunar sites which we think would be if most interest to tourists. I have taken the map of the Moon and have envisioned a line of roads that would link these sites into a single Grand Tour. From that, I have also identified a set of secondary roads. Those would mostly be of the edge of the large basins such that passengers in an electric vehicle could quickly drive on relatively flat roads yet have the views of the hills on the rims of the basins to view.
DevelopSpace.info/roads
Could you imagine a similar Grand Tour on Mars? What would be the most interesting sites? Would there be just a single Grand Tour or, given the size of Mars, would there need to be a set of tours where visitors would tour for a few weeks, return to the base/settlement for a while and then head out for the next tour?
DougSpace: Mars has a land area equal to the land area of the Earth (continents only). You can of course do a grand tour there, but it will require a lot of travel time. Better to break it down into separate locations.
Maybe you should email me about this.