Radar data from Zhurong finds no ice to a depth of 260 feet
Chinese scientists today finally published their results from the ground-penetrating radar instrument on their Mars rover Zhurong, revealing that to a depth of 260 feet (80 meters), it detected no clear signal of water ice.
Figure 2 of their paper, posted above, summarizes their results. It shows the radar profile to 328 feet (100 meters) depth along Zhurong’s route, as shown in the map to the right, with the last bit of its recent travels ending somewhere in the blue circle. From the paper:
Our low-frequency radar imaging profile shows radar signals within the depth range of 0–80 m (Fig. 2a), precluding the existence of a water-rich layer within this depth range as the existence of water would strongly attenuate the radar signals and diminish the visibility of deeper reflections. The estimated low (less than 9) dielectric permittivity (Fig. 2c) further supports the absence of a water-rich layer as water-bearing materials typically have high (greater than 15) dielectric permittivity.
We further tested this assessment with thermal considerations by conducting a heat conduction simulation based on available thermal parameters estimated from previous studies (Methods). Our thermal simulation results … show that the Zhurong landing area has an annual average temperature of around 220K in the RoPeR detection depth range, which is much lower than the freezing point of pure water (273K), and also lower than the eutectic temperatures of typical sulfate and carbonate brines, but slightly above those of perchlorate brine systems. This observation suggests that the shallow subsurface of the Zhurong landing area could not stably contain liquid water nor sulfate or carbonate brines, consistent with the radar imaging result.
The data suggests that below the surface topsoil layer, the regolith, there are two distinct layers of material that the scientists interpret as possible evidence of past catastrophic floods. That conclusion however is very very uncertain. The main take-away is that in the northern lowland plains of Utopia Planitia at 25 degrees north latitude, where Zhurong landed, Mars is definitely a dry desert, with no water close to the surface.
This data also suggests that if you establish a colony anywhere in Mars’ dry equatorial regions within 30 degrees latitude of the equator, you will likely have to travel north or south a considerable distance to get to easily accessible ice. The global map of Mars below shows the regions where ice is most evident, north and south of 30 degrees latitude.
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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.
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Chinese scientists today finally published their results from the ground-penetrating radar instrument on their Mars rover Zhurong, revealing that to a depth of 260 feet (80 meters), it detected no clear signal of water ice.
Figure 2 of their paper, posted above, summarizes their results. It shows the radar profile to 328 feet (100 meters) depth along Zhurong’s route, as shown in the map to the right, with the last bit of its recent travels ending somewhere in the blue circle. From the paper:
Our low-frequency radar imaging profile shows radar signals within the depth range of 0–80 m (Fig. 2a), precluding the existence of a water-rich layer within this depth range as the existence of water would strongly attenuate the radar signals and diminish the visibility of deeper reflections. The estimated low (less than 9) dielectric permittivity (Fig. 2c) further supports the absence of a water-rich layer as water-bearing materials typically have high (greater than 15) dielectric permittivity.
We further tested this assessment with thermal considerations by conducting a heat conduction simulation based on available thermal parameters estimated from previous studies (Methods). Our thermal simulation results … show that the Zhurong landing area has an annual average temperature of around 220K in the RoPeR detection depth range, which is much lower than the freezing point of pure water (273K), and also lower than the eutectic temperatures of typical sulfate and carbonate brines, but slightly above those of perchlorate brine systems. This observation suggests that the shallow subsurface of the Zhurong landing area could not stably contain liquid water nor sulfate or carbonate brines, consistent with the radar imaging result.
The data suggests that below the surface topsoil layer, the regolith, there are two distinct layers of material that the scientists interpret as possible evidence of past catastrophic floods. That conclusion however is very very uncertain. The main take-away is that in the northern lowland plains of Utopia Planitia at 25 degrees north latitude, where Zhurong landed, Mars is definitely a dry desert, with no water close to the surface.
This data also suggests that if you establish a colony anywhere in Mars’ dry equatorial regions within 30 degrees latitude of the equator, you will likely have to travel north or south a considerable distance to get to easily accessible ice. The global map of Mars below shows the regions where ice is most evident, north and south of 30 degrees latitude.
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.
” . . . summaries their results. ”
Hmm. I had thought the word to be ‘summarizes’, or ‘summarises’, depending on where you learned English. ‘Summaries’ would be a collection of the singular summary, perhaps.
Blair Ivey: Typo. Now fixed. Thank you.