Conscious Choice cover

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.  
Conscious Choice 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.


Available everywhere for $3.99 (before discount) at Amazon, Barnes & Noble, and 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.

The wavy and beautiful edge of the northern ice cap of Mars

The scarp of the north pole icecap on Mars
Click for full image.

Cool image time! The photo to the right, cropped and reduced to post here, was taken on August 7, 2021 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows the many layered scarp that forms the edge of the northern polar ice cap on Mars, probably more than 2,000 feet high.

Those layers are significant, as they indicate the many climate cycles that scientists think Mars has undergone over the eons as the red planet’s rotational tilt, or obliquity, rocked back and forth from 11 degrees inclination to as much as 60 degrees. At the extremes, the ice cap was either growing or shrinking, while today (at 25 degrees inclination) it appears to be in a steady state.

Why the layers alternate light and dark is not known. The shift from lighter colors at the top half and the dark bottom half marks the separation between the top water ice cap and what scientists label the basal unit. It also marks some major change in Mars’ climate and geology that occurred about 4.5 million years ago.

Overview map

The yellow cross on the overview map to the right indicates the location of this scarp. Because the pole’s scarps near the bottom of this map, where this photo was taken, tend to be less steep, most of the seasonal avalanches that occur in the spring are found along the scarps near the top of the map.

The origin of the hollow, where the scarp is retreating faster, is also unknown. For some reason something caused more erosion at this point. If it was an avalanche in the far past, all evidence of that event is gone. That the basal unit shows no such erosion suggests the origin is much more complicated than an avalanche.

One not obvious detail about this part of Mars is its daily weather. Though this is springtime and the Sun is out, it is very cold here, far colder than the coldest places on Earth. Though temperatures can get above freezing in the equatorial regions, at the poles that almost never happens. The planet’s average temperature globally is -81 degrees Fahrenheit. This means that at this spot the temperature when this photo was taken was likely well below zero degrees Fahrenheit, probably by many tens of degrees.


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