Click for full image.
Today’s cool image once again illustrates how Mars is far from a waterless planet. Instead, there is strong evidence that water ice can be found across most of the Red Planet’s surface, excluding the equatorial regions lower than 30 degrees latitude.
The photo to the right was taken on September 11, 2021 by the wide view context camera on Mars Reconnaissance Orbiter (MRO). It shows a 6-mile-wide unnamed crater on Mars, located at 35 degrees south latitude, with what appears to be a glacier in its interior, flowing to the southwest towards several breaches in the crater’s southwest rim. Several of those breaches now sit higher than the flow, suggesting that the glacier itself was once higher and flowed out of those gaps. Now the level has dropped, and the only place the glacier exits the crater is the central gap at the center of the white rectangle.
That white rectangle marks the area covered by a recent MRO high resolution image, taken on March 29, 2022 and cropped and reduced to post below.
Click for full image.
The close-up clearly shows what looks like a very typical glacial flow exiting the crater at this gap and working its way to the southwest along the valley it has carved. The parallel lines visible on that valley’s southern slopes, as well as the older breaches to the north and south, further suggest that this glacier was once higher. Each line marks the passing of one Martian climate cycle, thought to be caused by the wide swings of the planet’s rotational tilt, from 11 to 60 degrees. When the planet’s tilt is low, the poles are warmer than the mid-latitudes. Water migrates from the poles to those mid-latitudes where it falls as snow on these glaciers to make them grow. When the planet’s tilt is high, the situation reverses, and the water sublimates from the mid-latitudes to the poles, and the glaciers begin to shrink.
Today, Mars is tilted 25 degrees, so scientists believe the situation is in a steady-state, with the glaciers neither growing nor shrinking.
The overview map to the right marks this crater’s location with the black cross. The cratered region to the east of Hellas Basin is one of several on Mars where scientists have detected large numbers of glacial features (see the global Mars map in this August 1, 2022 post). The photos of this crater are simply another example.
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.