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Monument Valley on Mars

Monument Valley on Mars
Click for full image.

Today’s cool image is located near the Martian equator, in the middle of Arabia Terra, the most extensive region of the transition zone between the low northern plains and the southern cratered highlands. Taken on May 9, 2020 by the high resolution camera on Mars Reconnaissance Orbiter (MRO) and cropped to post here, the photo shows some layered mesas surrounded by a terraced and scalloped terrain with dust filling the low spots.

This is likely to be a very dry place on Mars. At only 2 degrees north of the equator, the evidence so far suggests that if there is a buried ice table (like the water table on Earth), it will be much deeper than at higher latitudes. The terrain reflects this, looking reminiscent of Monument Valley in the American southwest. In fact, the satellite image below, which I grabbed from MapQuest, shows a typical mesa in Monument Valley.

Monument Valley on Earth

Shown at about the same scale as the martian photo above, the similarities are striking. Both have layers, tall mesas, and dry terrain. The differences are also important. The Earth mesas show evidence of water erosion by their softened edges as well as the dry streambeds along the big mesa’s edges. On Earth there are trees in those dry streambeds. Earth also has dust, but no scalloped terrain, at least none visible at this scale.

Ironically, the cause of the erosion that created these mesas in both places is possibly quite similar, wind in recent eons but possibly water/ice far in the past, when the entire planet’s climate was different. For Mars this remains a guess.

Overview of Arabia Terra

The overview map to the right gives the larger context. The white cross is the location of these mesas. Arabia Terra is the large green region east of Chryse Planitia and Valles Marineris.

My guess that this location is dry comes not only because it is at the equator. It is also quite far from the northern lowlands and is very close to the cratered highlands. If an intermittent ocean in the northern lowlands once lapped against Arabia Terra, its shoreline ebbing and flowing as the Martian climate changed, that shoreline would have been far to the north and west of this location. Water and ice might have once been here, but that was likely a very very long time ago.

Pioneer cover

From the press release: From the moment he is handed a possibility of making the first alien contact, Saunders Maxwell decides he will do it, even if doing so takes him through hell and back.

Unfortunately, that is exactly where that journey takes him.

The vision that Zimmerman paints of vibrant human colonies on the Moon, Mars, the asteroids, and beyond, indomitably fighting the harsh lifeless environment of space to build new societies, captures perfectly the emerging space race we see today.

He also captures in Pioneer the heart of the human spirit, willing to push forward no matter the odds, no matter the cost. It is that spirit that will make the exploration of the heavens possible, forever, into the never-ending future.

Available everywhere for $3.99 (before discount) at amazon, Barnes & Noble, all ebook vendors, or direct from the ebook publisher, ebookit. And if you buy it from ebookit you don't support the big tech companies and I get a bigger cut much sooner.


  • Chris

    Hi Bob,

    Are there any estimates on the heights of these features on Mars?
    Do you know the height of the feature shown on Earth’s Monument Valley?


  • Chris: I am presently trying to get the software set up so that I can check heights, as you ask. Not there yet.

    As for Monument Valley, the buttes range from 400 to 1000 feet in height. See here. I suspect the buttes at this location on Mars are comparable.

  • Chris

    Thanks Bob

  • MDN

    If you zoom in real tight on the channel between the bottom and middle mesa I think we could see Martian Gump lamenting that he’s tired now : )

  • Ken Franks

    I’d hike that!

  • Doug in COS

    Thank you Bob for your insights and analysis, I really enjoy reading and pondering the implications of everything in the universe beyond our amazing planet. I’ve had your site bookmarked for awhile (hat tip AoS) and have shared it with a few like minded friends. Those Martian dust devils…just wow. Regards

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