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A Martian “glacier” made of volcanic ash

A Martian
Click for full image.

Of the numerous cool images I’ve posted on Mars, many have documented the growing evidence that in the mid-latitudes of the Red Planet are many buried glaciers of ice.

Today’s cool image to the right, rotated, cropped and reduced to post here, shows something that at first might resemble the features one would expect from an ice glacier, but in reality is actually a flow of volcanic ash being blown almost like a river, with the prevailing winds blowing from the south to the north.

The photo was taken by the high resolution camera on Mars Reconnaissance Orbiter (MRO) on November 1, 2020. The location, very close to the equator and in the transition zone dubbed the Cerberus Plains, is also smack dab between Mars’s biggest volcanoes, a region I like to dub Mars’s volcano country. The overview map below gives the context.

Medusae Fossae Formation in volcano country

The white cross indicates the photo’s location, right in the midst of the Medusae Fossae Formation, the largest volcanic ash deposit on Mars. This particular section of the Medusae ash deposit is located on a large uplifted region called Lucas Planum, a huge mound about 540 miles across and encompasses the eastern outlined section of the Medusae Fossae Formation where the white cross is placed.

I’ve posted a number of similar images showing the wind-blown erosion of the Medusae Fossae Formation (see for example here and here). The features all have a similar appearance, reminiscent of the carved mesas of the American southwest, but much softer and more sculpted. It is my impression that this is a region of softly piled sand and dust, easily dug but difficult to build on because the ground is weakly structured and so easily eroded. Imagine the difficulties of building a home on a beach.

Scientists today believe that much of the dust we find on Mars comes from the Medusae. What they don’t yet know is when it was created, from what volcano or volcanoes, and in how many different eruptions. To answer those questions will require in situ observations, including a gathering of many samples that all can be dated.

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.

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