The drying out of Mars’ tropics
Click for original image.
Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on June 26, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). The science team calls the features surrounding these small 20 to 60 foot high hills “polygon features,” an apt description and a geological feature that is seen in many places on Mars.
When these features are found in the icy higher latitudes, it is believed they are formed in connection to the freeze-thaw cycle that causes cracks in the near surface ice. When found in the dry equatorial regions, where these polygons are located, they are usually thought to be ancient evidence of past standing water that left behind these cracks, much like the cracks seen in mud after the water has evaporated away on Earth.
The formation of these tiny hills is a bit more complex.
The red dot on the overmap to the right marks the location of these polygons, inside 85-mile wide Galilaei Crater. Scientists believe catastrophic floods coming down from Valles Marineris filled the crater with a lake, as well as leaving behind the nearby inland sea noted in blue on the map. Later that lake drained out through a breach in the crater’s southwestern wall, leaving behind its cracked floor with many of these strange little hills in its southern half.
These cracks have been here for a long while, but it is also possible that during the wide swings in Mars’ rotational tilt, from 11 to 60 degrees the Martian tropics might have seen many cycles of wetter weather, even after those catastrophic floods were long gone. The polygons here might thus not be from those floods, but from later cycles.
And of course, there is always the question of whether these features were caused by liquid water or ice, since the existence of running liquid water on the surface of Mars at any time in the past remains unproven. Based on the known data the climate has apparently always been too cold and the atmosphere too thin.
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In 2020 when the world panicked over COVID I wrote that the panic was unnecessary, that the virus was apparently simply a variation of the flu, that masks were not simply pointless but if worn incorrectly were a health threat, that the lockdowns were a disaster and did nothing to stop the spread of COVID. Only in the past year have some of our so-called experts in the health field have begun to recognize these facts.
Your help allows me to do this kind of intelligent analysis. I take no advertising or sponsors, so my reporting isn't influenced by donations by established space or drug companies. Instead, I rely entirely on donations and subscriptions from my readers, which gives me the freedom to write what I think, unencumbered by outside influences.
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Click for original image.
Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on June 26, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). The science team calls the features surrounding these small 20 to 60 foot high hills “polygon features,” an apt description and a geological feature that is seen in many places on Mars.
When these features are found in the icy higher latitudes, it is believed they are formed in connection to the freeze-thaw cycle that causes cracks in the near surface ice. When found in the dry equatorial regions, where these polygons are located, they are usually thought to be ancient evidence of past standing water that left behind these cracks, much like the cracks seen in mud after the water has evaporated away on Earth.
The formation of these tiny hills is a bit more complex.
The red dot on the overmap to the right marks the location of these polygons, inside 85-mile wide Galilaei Crater. Scientists believe catastrophic floods coming down from Valles Marineris filled the crater with a lake, as well as leaving behind the nearby inland sea noted in blue on the map. Later that lake drained out through a breach in the crater’s southwestern wall, leaving behind its cracked floor with many of these strange little hills in its southern half.
These cracks have been here for a long while, but it is also possible that during the wide swings in Mars’ rotational tilt, from 11 to 60 degrees the Martian tropics might have seen many cycles of wetter weather, even after those catastrophic floods were long gone. The polygons here might thus not be from those floods, but from later cycles.
And of course, there is always the question of whether these features were caused by liquid water or ice, since the existence of running liquid water on the surface of Mars at any time in the past remains unproven. Based on the known data the climate has apparently always been too cold and the atmosphere too thin.
Readers!
Please consider supporting my work here at Behind the Black. Your support allows me the freedom and ability to analyze objectively the ongoing renaissance in space, as well as the cultural changes -- for good or ill -- that are happening across America. Fourteen years ago I wrote that SLS and Orion were a bad ideas, a waste of money, would be years behind schedule, and better replaced by commercial private enterprise. Only now does it appear that Washington might finally recognize this reality.
In 2020 when the world panicked over COVID I wrote that the panic was unnecessary, that the virus was apparently simply a variation of the flu, that masks were not simply pointless but if worn incorrectly were a health threat, that the lockdowns were a disaster and did nothing to stop the spread of COVID. Only in the past year have some of our so-called experts in the health field have begun to recognize these facts.
Your help allows me to do this kind of intelligent analysis. I take no advertising or sponsors, so my reporting isn't influenced by donations by established space or drug companies. Instead, I rely entirely on donations and subscriptions from my readers, which gives me the freedom to write what I think, unencumbered by outside influences.
You can support me either by giving a one-time contribution or a regular subscription. There are four ways of doing so:
1. Zelle: This is the only internet method that charges no fees. All you have to do is use the Zelle link at your internet bank and give my name and email address (zimmerman at nasw dot org). What you donate is what I get.
2. Patreon: Go to my website there and pick one of five monthly subscription amounts, or by making a one-time donation.
3. A Paypal Donation or subscription:
4. Donate by check, payable to Robert Zimmerman and mailed to
Behind The Black
c/o Robert Zimmerman
P.O.Box 1262
Cortaro, AZ 85652
You can also support me by buying one of my books, as noted in the boxes interspersed throughout the webpage or shown in the menu above.
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