Martian craters or volcanoes?
Click for original image.
Cool image time! The picture to the right, cropped and reduced to post here, was taken on June 30, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). The scientists label these features “cones” because many of the depressions sit on top of a mound or hill, suggesting some form of volcanic feature, either from erupting lava, ice, or mud.
Yet, are they volcanoes? Some or even many could instead be impact craters, created when a asteroid broke up during infall, creating a spray of bolides. Erosion of surrounding terrain can create what scientists call pedestal craters, but if all these craters were from an impact than all would either be pedestal craters, or not. Instead, we have a mix of some craters above and others level with the terrain.
The white dot on the overview map to the right, about 100 miles northwest of the landing site for China’s Zhurong rover, marks this spot. Though in the dry equatorial regions below 30 degrees latitude, the features in this image suggest that either some water might still exist deep underground, or it has disappeared but not that long ago.
Thus, the answer to the question in the headline might be “Yes!” The cones could be evidence of past mud/ice volcanic activity, while the craters at ground level might be from impact.
In fact, finding out for sure if these cones are mud/ice volcanoes is one of the questions American scientists hoped Zhurong might answer, as it landed not far from one such cone to the north and could have gone there to inspect it. Instead, the Zhurong team chose to head south, and never got near any similar cones.
Thus, the solution to this geological mystery remains. These could be mud volcanoes, they could be impact craters, or they could be a mix of both. Or they might even be some third geological process unique to Mars that geologists don’t at this time understand.
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, cropped and reduced to post here, was taken on June 30, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). The scientists label these features “cones” because many of the depressions sit on top of a mound or hill, suggesting some form of volcanic feature, either from erupting lava, ice, or mud.
Yet, are they volcanoes? Some or even many could instead be impact craters, created when a asteroid broke up during infall, creating a spray of bolides. Erosion of surrounding terrain can create what scientists call pedestal craters, but if all these craters were from an impact than all would either be pedestal craters, or not. Instead, we have a mix of some craters above and others level with the terrain.
The white dot on the overview map to the right, about 100 miles northwest of the landing site for China’s Zhurong rover, marks this spot. Though in the dry equatorial regions below 30 degrees latitude, the features in this image suggest that either some water might still exist deep underground, or it has disappeared but not that long ago.
Thus, the answer to the question in the headline might be “Yes!” The cones could be evidence of past mud/ice volcanic activity, while the craters at ground level might be from impact.
In fact, finding out for sure if these cones are mud/ice volcanoes is one of the questions American scientists hoped Zhurong might answer, as it landed not far from one such cone to the north and could have gone there to inspect it. Instead, the Zhurong team chose to head south, and never got near any similar cones.
Thus, the solution to this geological mystery remains. These could be mud volcanoes, they could be impact craters, or they could be a mix of both. Or they might even be some third geological process unique to Mars that geologists don’t at this time understand.
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
I like occam‘s razor, the simplest explanation…
Due to the lack of large volcanic features, or uneven lava landscape… The lack erosion features, and the over abundance of what appears to be fine volcanic ash that was once much deeper but only the heavier grains didn’t blow away… my vote is for old meteor impacts that compressed and solidified what appears to be about 100 feet? of fine volcanic ash.
Over the eons, the ash blew away badly eroding the smaller pedestals, and exposing old impact Craters under the ash. I can see the small Craters inside both the surface ones and the pedestal Craters indicating they’ve been there a long time. A perfectly shaped crater is the only recent one I see to the left of the picture. Useful as a comparison.
Although there’s no brain terrain in this picture, i’ve been wondering how such unusual features can exist?
The best explanation I have as yet, is the clue that these features are usually on large unusually deep lava flows. The surface on a cold planet will quickly harden a lava flow until pressure from underneath will lift and crack the surface in waves, but in random sections like the breaking up of a ice flow on a river. Or the shattering of safety glass.
Heavier large sections will sink slightly into the molten lava forming the brain terrain before the viscous lava hardens on a cold low gravity planet.
Now I can quit thinking about it and focus on something else. (I do like a good mystery)