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Layers upon layers of Martian volcanic ash

Layers upon layers of Martian volcanic ash
Click for full image.

Today’s cool image provides I think a hint at the vast amount of time that has passed on Mars, allowing uncounted major events to occur which each lay down a bit of the geological history, a history that is now piled up on the surface so deeply that it will take decades of research to untangle it.

The photo to the right, cropped and reduced to post here, was taken on December 23, 2020 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows the layered nature of the Medusae Fossae Formation, the largest volcanic ash deposit on Mars (about the land area of India) and thought by some to be the source of most of the dust across the entire red planet.

Overview map

The white cross marks the location of this photo in the overview map to the right. The white blobs are quakes detected by the InSight lander’s seismometer 1,100 miles to the west. The black dots in the blobs are the quakes’ epicenters.

At 3 degrees south latitude this is in Mars’ dry equatorial regions. What we see here is a thick covering of ash many feet deep that over eons has been shaped and eroded by wind. The wind has not only carved these mesas, it has revealed that the ash was laid down in many distinct layers, suggesting that each layer was a different volcanic event.

We don’t know the volcano or volcanoes that produced each ash deposit, only that this immense ash deposit is well placed between all of Mars’ biggest volcanoes. However, that each layer was a different event, and that the events were likely far away, suggests that the events were massive, and many.

Mars was a very different place when these volcanoes were active. Moreover, that active period apparently lasted a very long time, probably exceeding a billion years. So long in fact that it is difficult for the human mind to grasp.

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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