The unbelievably rough and wind-swept surface of Mars’ Greenheugh pediment
Click for full image.
Since my last update on the travels of the Mars rover Curiosity on February 22, 2022, the rover has been been creeping ever so slowly westward across a plateau that scientists have dubbed the Greenheugh pediment.
Scientists have known for years that the surface of the pediment was going to be rough going. This panorama taken by Curiosity when it first climbed up to the pediment in March 2020 to take a peek before retreating revealed that roughness starkly.
In truth, since beginning its traverse of that pediment in February, the Curiosity team has found the ground not only as rough as expected, but beautiful in a strange sort of way, as illustrated by the March 20, 2022 photo to the right, reduced to post here. As Lauren Edgar, Planetary Geologist at USGS Astrogeology Science Center, noted yesterday in a Curiosity update that featured this image:
Click for interactive map.
Curiosity is investigating the different surface expressions of the Greenheugh pediment, and the weekend drive put the rover right next to some “gator-back terrain” – some evenly spaced ridges with a blocky expression, as seen in the above Navcam image. Today’s one sol plan is focused on a close encounter with one of these ridges through contact science and remote sensing.
The look of this gator-back terrain is caused first by its blocky nature. The top layer of the Greenheugh pediment is not very structurally strong, so it has broken into many small pieces over time. Second, the very thin wind of Mars has slowly carved those blocks, smoothing their surface.
On the overview map to the right, the dotted red line indicates Curiosity’s future planned route. The white dotted line indicates its actual route, with each dot marking a stopping point. As you can see, since climbing up onto the pediment, Curiosity has been traveling very slowly, moving in tiny steps as it carefully picks its way between rocks so as to avoid damaging its already badly dinged wheels.
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 or from any other book seller. If you want an autographed copy the price is $60 for the hardback and $45 for the paperback, plus $8 shipping for each. Go here for purchasing details. 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 full image.
Since my last update on the travels of the Mars rover Curiosity on February 22, 2022, the rover has been been creeping ever so slowly westward across a plateau that scientists have dubbed the Greenheugh pediment.
Scientists have known for years that the surface of the pediment was going to be rough going. This panorama taken by Curiosity when it first climbed up to the pediment in March 2020 to take a peek before retreating revealed that roughness starkly.
In truth, since beginning its traverse of that pediment in February, the Curiosity team has found the ground not only as rough as expected, but beautiful in a strange sort of way, as illustrated by the March 20, 2022 photo to the right, reduced to post here. As Lauren Edgar, Planetary Geologist at USGS Astrogeology Science Center, noted yesterday in a Curiosity update that featured this image:
Click for interactive map.
Curiosity is investigating the different surface expressions of the Greenheugh pediment, and the weekend drive put the rover right next to some “gator-back terrain” – some evenly spaced ridges with a blocky expression, as seen in the above Navcam image. Today’s one sol plan is focused on a close encounter with one of these ridges through contact science and remote sensing.
The look of this gator-back terrain is caused first by its blocky nature. The top layer of the Greenheugh pediment is not very structurally strong, so it has broken into many small pieces over time. Second, the very thin wind of Mars has slowly carved those blocks, smoothing their surface.
On the overview map to the right, the dotted red line indicates Curiosity’s future planned route. The white dotted line indicates its actual route, with each dot marking a stopping point. As you can see, since climbing up onto the pediment, Curiosity has been traveling very slowly, moving in tiny steps as it carefully picks its way between rocks so as to avoid damaging its already badly dinged wheels.
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 or from any other book seller. If you want an autographed copy the price is $60 for the hardback and $45 for the paperback, plus $8 shipping for each. Go here for purchasing details. 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
Great image! Initial guess would be a comparison with some types of volcanic rock here, which breaks into regular shapes when it cools. Best-known example would be Devil’s Postpile in the Sierra Nevada near Mammoth, but not all volcanic flow units break into hexagonal shapes, and this may be an example of that.
Speaking of wind, tornadoes are on the ground in New Orleans…Stennis Space Center strike at 8:25 CDT. It is now 8:19 p.m. CDT!
Here’s hoping that the pediment doesn’t prove to be an impediment.
More on the NOLA twister that hit the Lower Ninth Ward-with footage from Brad Cheramie, Preston Trahan at Storyfull and Scot Pilie at twitter.
Brian Emfinger filmed a truck in Texas that drove away after being rolled. As per “Says You!” the term ‘weather’ is one of few words that can stand for polar opposite meanings:
“The scalloped pediment can weather any one Martian dust storm-but over deep time, the rock will weather away even in that rarified atmosphere.”