Click for full image.
Cool image time! The photo to the right, rotated, cropped, and reduced to post here, was taken on November 29, 2020 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). Labeled simply as “periglacial survey,” it is one of almost two hundred such images taken by MRO over the years, almost all of which are in the high latitudes above 60 degrees, with most being in the southern hemisphere. Most appear to be close to or above Mars’s Arctic Circle, which means these are locations that will see little or no sunlight for a portion of the year.
I have been unable to contact the scientists doing this survey, so I will have to make an educated guess as to its purpose and goals. “Periglacial” refers to the outer fringes or margin of a glacier or large ice sheet. Thus, in the context of this survey, the scientists appear to be studying places where they think the Martian high latitude ice sheets are beginning to sublimate away. Today’s photo is a good example. It is located at 67 degrees south latitude, in the southern cratered highlands but in an area that appears to be relatively free of craters. Instead, the terrain appears somewhat flat with only periodic depressions and scarps. The MRO context camera photo below of the same area, rotated, cropped, and expanded to post here, illustrates this.
Click for full image.
The black box marks the area covered by the close-up photo. As you can see, what looked like an east-west channel in the close-up was merely a longer enclosed depression.
In fact, the whole region reminds me of what you see if you finely spray hot water on a sheet of ice. Patches begin to melt away randomly, producing holes and depressions.
In the close-up one also gets the strong sense that everything here is either frozen ice or is dust and dirt that is impregnated within it, so much so that everything has become smoothed as the ice has gone through numerous cycles of freezing and sublimation over the eons. There are no dunes, and though the dark streaks indicate dust devil tracks there certainly appears to be little surface dust.
The photo and its features, as well as this entire periglacial survey, strongly invokes a vision of a very icy Mars in its high latitudes. While scientists have found many glacial features in the latitude bands from 30 to 60 degrees latitude, what this photo suggests is that at higher latitudes the ground is almost entirely covered by an ice sheet.
As I’ve said before, Mars is a desert like Antarctica, icy, cold, and very dry. In building future colonies that coldest place on Earth probably gives us the best analogy for the environment on Mars.
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.
All editions available at Amazon, Barnes & Noble, and all book vendors. The ebook can be purchased direct from my ebook publisher, ebookit, in which case you don't support the big tech companies and I get a bigger cut much sooner. Note that the price for the ebook, $3.99, goes up to $5.99 on September 1, 2022.
Autographed printed copies are also available at discount directly from me (hardback $24.95; paperback $14.95). Just email me at zimmerman @ nasw dot org.