The flowing formations of Lethe Vallis
Cool image time! The Mars Reconnaissance Orbiter science team yesterday released several new images. Below is just one, cropped and reduced in resolution to post here. It shows a large flow channel called Lethe Vallis, formed first by lava, then hit by an impact which created a walled crater in its middle. Flood waters then followed, creating the tear-shaped dune surrounding the crater. In addition, erosion exposed the dark lava basalt below the surface on the edge of that tear-shaped dune. Within the crater itself can be seen ripple dunes formed by wind. As the scientists note,
This single image thus contains features formed by periglacial, volcanic, fluvial, impact, aeolian and mass wasting processes, all in one place.
Be sure to check out the full image.
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 Mars Reconnaissance Orbiter science team yesterday released several new images. Below is just one, cropped and reduced in resolution to post here. It shows a large flow channel called Lethe Vallis, formed first by lava, then hit by an impact which created a walled crater in its middle. Flood waters then followed, creating the tear-shaped dune surrounding the crater. In addition, erosion exposed the dark lava basalt below the surface on the edge of that tear-shaped dune. Within the crater itself can be seen ripple dunes formed by wind. As the scientists note,
This single image thus contains features formed by periglacial, volcanic, fluvial, impact, aeolian and mass wasting processes, all in one place.
Be sure to check out the full image.
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
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