A 10-mile-long avalanche on Mars
Click for original image.
Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on November 8, 2025 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows only three miles of a ten-mile-long avalanche inside the solar system’s largest canyon, Valles Marineris.
The white dot on the overview map above marks the location. In the inset the white rectangle indicates the area covered by the picture to the right. I have indicated the avalanche’s full extent beyond this.
Overall, the landslide fell about one mile along those ten miles. That there are about a dozen small craters on top of the slide tells us this happened quite a long time ago.
As always, the scale of Valles Marineris boggles the mind. Though this avalanche fell about 5,000 feet (the same depth of the south rim of the Grand Canyon), that drop only covered one fifth of Valles Marineris’s depth. At this point, from the rim to the floor the elevation difference is about 23,000 feet, which would place the rim among the 100 highest mountains on Earth. And of course, this is only one small spot in this gigantic canyon that runs 2,500 miles east-to-west, with its depth about the same that entire length.
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 original image.
Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on November 8, 2025 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows only three miles of a ten-mile-long avalanche inside the solar system’s largest canyon, Valles Marineris.
The white dot on the overview map above marks the location. In the inset the white rectangle indicates the area covered by the picture to the right. I have indicated the avalanche’s full extent beyond this.
Overall, the landslide fell about one mile along those ten miles. That there are about a dozen small craters on top of the slide tells us this happened quite a long time ago.
As always, the scale of Valles Marineris boggles the mind. Though this avalanche fell about 5,000 feet (the same depth of the south rim of the Grand Canyon), that drop only covered one fifth of Valles Marineris’s depth. At this point, from the rim to the floor the elevation difference is about 23,000 feet, which would place the rim among the 100 highest mountains on Earth. And of course, this is only one small spot in this gigantic canyon that runs 2,500 miles east-to-west, with its depth about the same that entire length.
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