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A close-up of the giant crack that almost splits Mars

A close-up of the crack that splits Mars
Click for original image.

Cool image time! The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on June 28, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). The intended science focus of the image is likely the floor of this canyon on the lower right, showing what appears to be a patch of uprised topography surrounded by what looks like glacial debris, which at this latitude of 39 degrees north is expected on Mars.

The grade at this location is downhill to the southwest, so if this is a glacier it is flowing in that direction.

The cliff is about 3,000 feet high, dropping that distance in about a mile and a half. Thus, this is only slightly less steep than the very steep cliff wall of the caldera of Olympus Mons, highlighted as a cool image two days ago.

What makes this canyon interesting — besides its spectacular scenery — is its larger context, recognized when one looks at this location from afar and thus sees how it shaped a vast portion of the global surface of Mars.

Overview map

The black dot on the overview map to the right marks the location of this canyon, in the middle of the gracefully curving series of parallel canyons dubbed Tempe Fossae.

The larger significance of these parallel canyons is indicated by the long white line, delineating the 3,500-mile-long fault line that runs through three of the red planet’s biggest volcanoes, and likely explains their relationship and formation.

While to the southwest that fault line caused the growth of three gigantic volcanoes, at this location it expresses itself simply as this fissured terrain, with the curves suggesting some later tectonic process that applied sideways pressure to warp the cracks. Regardless, this canyon is part of one of Mars’ largest geological features, a crack that some scientists believe might have been caused by the giant impact that created Helas Basin on the opposite side of the planet.

Genesis cover

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

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