Click for full image.
Cool image time! As my regular readers well know, I am a caver, and am thus always interested when the high resolution camera on Mars Reconnaissance Orbiter (MRO) takes a close-up of a pit that might also be an entrance to a cave.
The photo to the right, cropped and reduced to post here, was part of the most recent image release from MRO, but was boringly labeled “Arabia Terra” after the region where it is located, one of the largest transition zones on Mars between the northern lowland plains and the southern cratered highlands. When I took a close look, what I found was an intriguing string of pits whose arrangement is strikingly reminiscent of a river tributary system.
The white box indicates one section that I have zoomed into, as shown below.
Gosh, that sure looks like there was an underground drainage, flowing from the right to the left, with two tributaries coming to a confluence that on the wider image above continues to the north and west until it combines with another set of tributaries and then heads west. Whatever had flowed underground had eventually eroded a large enough passage for the ceiling to collapse in multiple places along its length.
Of course, we have no idea if these pits are skylights into a volcanic lava tube, or a former water passage. The low latitude, only 5 degrees north of the equator, argues against liquid water, but then, this is also the same latitude as the giant canyon Valles Marineris, which scientists think might have been formed by catastrophic floods.
The overview map on the right provides this context. The red cross indicates the location of this image. The blue cross indicates the area the rover Opportunity explored.
The implied direction of the underground drainage, to the west, also makes sense. The general downward grade for Arabia Terra is to the west and north.
Finally, the color strip in the top photo provides one more intriguing detail. The ground surrounding one string of pits is differently colored than the surrounding terrain, suggesting a different make-up. To my eye this looks like dust material that might have been blown from the pits, but that’s a pure guess.
Is there a cave system here? We do not know, though other research supports this hypothesis.
Now available in hardback and paperback as well as ebook!
From the press release: In this ground-breaking new history of early America, historian Robert Zimmerman not only exposes the lie behind The New York Times 1619 Project that falsely claims slavery is central to the history of the United States, he also provides profound lessons about the nature of human societies, lessons important for Americans today as well as for all future settlers on Mars and elsewhere in space.
Conscious Choice: The origins of slavery in America and why it matters today and for our future in outer space
, is a riveting page-turning story that documents how slavery slowly became pervasive in the southern British colonies of North America, colonies founded by a people and culture that not only did not allow slavery but in every way were hostile to the practice.
does more however. In telling the tragic history of the Virginia colony and the rise of slavery there, Zimmerman lays out the proper path for creating healthy societies in places like the Moon and Mars.
“Zimmerman’s ground-breaking history provides every future generation the basic framework for establishing new societies on other worlds. We would be wise to heed what he says.” —Robert Zubrin, founder of founder of the Mars Society.
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