The ancientness of rocks on Mars
Click for original image.
Cool image time! The picture to the right, cropped, reduced, and enhanced to post here, was taken on December 27, 2023 by the high resolution camera on the Mars rover Curiosity. It shows what is a somewhat typical rock found on the ground as Curiosity climbs Mount Sharp in Gale Crater.
Two features stand out. First, the many layers illustrate again the cyclical nature of Martian geology. Many sedimentary events occurred over a long time to create this rock, each cycle putting down a new layer, with some intervening time periods possibly removing layers as well. Such layering has now become evident in both ground photos taken by rovers as well as orbital images.
Second, the delicate nature of some layers indicates the incredibly slow erosion process on Mars, enhanced by the red planet’s one-third gravity. The atmosphere is incredibly thin, less than 0.1% of Earth’s. Yet given time the wind had been able to wear away the edges of this rock. The thin atmosphere and light gravity has also allowed some material to remain in a delicate manner that would be impossible on Earth.
Thus, for these thin flakes to have formed has required a great deal of time. The very nature of this rock speaks of an ancient terrain, shaped slowly by inanimate processes with no active life around to disturb things.
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, reduced, and enhanced to post here, was taken on December 27, 2023 by the high resolution camera on the Mars rover Curiosity. It shows what is a somewhat typical rock found on the ground as Curiosity climbs Mount Sharp in Gale Crater.
Two features stand out. First, the many layers illustrate again the cyclical nature of Martian geology. Many sedimentary events occurred over a long time to create this rock, each cycle putting down a new layer, with some intervening time periods possibly removing layers as well. Such layering has now become evident in both ground photos taken by rovers as well as orbital images.
Second, the delicate nature of some layers indicates the incredibly slow erosion process on Mars, enhanced by the red planet’s one-third gravity. The atmosphere is incredibly thin, less than 0.1% of Earth’s. Yet given time the wind had been able to wear away the edges of this rock. The thin atmosphere and light gravity has also allowed some material to remain in a delicate manner that would be impossible on Earth.
Thus, for these thin flakes to have formed has required a great deal of time. The very nature of this rock speaks of an ancient terrain, shaped slowly by inanimate processes with no active life around to disturb things.
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 think the Martian atmosphere is roughly 1% that of Earth, not 0.1% (one thousandth)
Mike,
That was my memory, too, but I looked it up in Wikipedia (that bastion of truth) and discovered that it is closer to 0.6%. They list it as 600 Pa, and Earth’s atmosphere is 100,000 Pa
https://en.wikipedia.org/wiki/Mars#Atmosphere
Yes Edward, but still closer to 1% than 0.1%. IIRC it varies with the seasons also.
Mike Borgelt and Edward: This is an example of why any writer should never state facts based solely on memory. I should have checked this before I wrote it. I have corrected the post, using the numbers Edward found.
Thank you both.
Those rock extensions make me wonder about “Mars Quakes”
Perhaps the larger Rock is decoupled form the ground.