Zhurong data suggests a more watery Martian environment more recently that previously thought
The graph comes from this paper [pdf], and shows the shift of Mars’
rotational tilt, or obliquity, for the past 80 million years.
Scientists analyzing data obtained by China’s Zhurong rover during its first four months on Mars have concluded that the Martian atmosphere in the northern lowland plains of Utopia Planitia has been more active hydrologically much more recently than previously believed.
You can read the paper here. From its conclusions:
Unlike the weak and friable thin veneer or crusty clods at previous landing sites for Mars Exploration Rovers and InSight lander, these rocks are more akin to the fractured duricrust observed at the Viking Lander 1 site. The thin and brittle layer of duricrust has been proposed to form by salt cementation via water vapor diffusion from the atmosphere. In contrast, duricrusts at Zhurong landing site appear to be more resistant to erosion, forming cliffs perched through loose soils in the surroundings, which require a substantial amount of liquid water rather than water vapor.
…The morphology and spatial extent of platy and bright-toned rocks investigated by the Zhurong rover argue for in situ formation and degradation of these rocks in the Amazonian-aged geological unit in southern Utopia Planitia. These observations suggest that aqueous activities may have persisted much longer than previously thought. Periodical climate cycles on Mars driven by obliquity oscillations are expected to result in a latitude-dependent distribution of ground ice over geologic history. Higher obliquities (>45°) could mobilize polar ice and form glaciers and water ice sheets at midlatitudes and stabilize ground ice at Zhurong landing site for extended periods of tens of thousand years when the obliquity exceeded 29° to 33°. The hydrated minerals and widespread salt cementations imply the presence of briny liquid water in the subsurface, which may have been generated by melting the ground ice during temporary climate perturbations (e.g., volcanism and impacts).
Obliquity refers to the planet’s rotational tilt, which fluctuates from 11 to 65 degrees, and is presently tilted at 25 degrees, only slightly different than Earth’s 23 degree tilt. Since Mars’ obliquity has exceed 29 degrees numerous times in the past 80 million years, as shown by the graph above, that means it was possible that this now dry equatorial region on Mars had seen plenty of surface water or ice as recently as a few million years ago, far more recently than the three billion years previously estimated.
For liquid water to have existed on the surface is still difficult, because Mars’ atmosphere would have been too thin and cold. However, if ice sheets had existed here, there is the possibility that the ice would have become liquid at the sheet’s base, and interacted with the ground in some manner to produce the duricrust now observed.
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.
The graph comes from this paper [pdf], and shows the shift of Mars’
rotational tilt, or obliquity, for the past 80 million years.
Scientists analyzing data obtained by China’s Zhurong rover during its first four months on Mars have concluded that the Martian atmosphere in the northern lowland plains of Utopia Planitia has been more active hydrologically much more recently than previously believed.
You can read the paper here. From its conclusions:
Unlike the weak and friable thin veneer or crusty clods at previous landing sites for Mars Exploration Rovers and InSight lander, these rocks are more akin to the fractured duricrust observed at the Viking Lander 1 site. The thin and brittle layer of duricrust has been proposed to form by salt cementation via water vapor diffusion from the atmosphere. In contrast, duricrusts at Zhurong landing site appear to be more resistant to erosion, forming cliffs perched through loose soils in the surroundings, which require a substantial amount of liquid water rather than water vapor.
…The morphology and spatial extent of platy and bright-toned rocks investigated by the Zhurong rover argue for in situ formation and degradation of these rocks in the Amazonian-aged geological unit in southern Utopia Planitia. These observations suggest that aqueous activities may have persisted much longer than previously thought. Periodical climate cycles on Mars driven by obliquity oscillations are expected to result in a latitude-dependent distribution of ground ice over geologic history. Higher obliquities (>45°) could mobilize polar ice and form glaciers and water ice sheets at midlatitudes and stabilize ground ice at Zhurong landing site for extended periods of tens of thousand years when the obliquity exceeded 29° to 33°. The hydrated minerals and widespread salt cementations imply the presence of briny liquid water in the subsurface, which may have been generated by melting the ground ice during temporary climate perturbations (e.g., volcanism and impacts).
Obliquity refers to the planet’s rotational tilt, which fluctuates from 11 to 65 degrees, and is presently tilted at 25 degrees, only slightly different than Earth’s 23 degree tilt. Since Mars’ obliquity has exceed 29 degrees numerous times in the past 80 million years, as shown by the graph above, that means it was possible that this now dry equatorial region on Mars had seen plenty of surface water or ice as recently as a few million years ago, far more recently than the three billion years previously estimated.
For liquid water to have existed on the surface is still difficult, because Mars’ atmosphere would have been too thin and cold. However, if ice sheets had existed here, there is the possibility that the ice would have become liquid at the sheet’s base, and interacted with the ground in some manner to produce the duricrust now observed.
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.
I thought some other study said Mars was drier than we thought
https://phys.org/news/2022-01-present-day-martian-groundwater-dries.amp