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User:Robertinventor/Email-Interview-with Vlada/Background Information

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TH2OR and TDEM

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Short summary

He explained that his TH2OR is a small device that lets you generate ultra low frequency radio waves, far below the frequency of radar. These waves are ideal for detecting salty brines, even if only slightly salty, well below the surface of a planet (the salt makes the brines more conducting and so easier to detect using radar). They can penetrate to a depth of kilometers.

The waves would be at least kilometers in wavelength up to thousands of kiloemters. It's not practical to use a normal antenna for this. It could use natural sources such as changes in the ionisphere, solar wind, or lightning. But there is another ingenious method widely used on Earth for geological surveying, to set a current looping around in a loop - then suddenly switch it off. This causeas an eddy current to propogate down into the ground a bit like a smoke ring, getting wider as it gets deeper. This gives the momentary very long wavelength radio waves, only for a short time as transietns, but broaad in bandwidth. The Russians planned to fly to Mars in their ill fated Mars 94 mission. This is what they plan to use. They will use natural sources as well if they are present but don't know enough about Mars to rely on them being there.

Details

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TH2OR would use Wikipedia:Ultra low frequency radio waves to detect deep subsurface brines. It is a method widely used for surveying on Earth, using frequencies far lower than for ground penetrating radar, typically in the range from a fraction of a Hertz to kilohertz. These are hard to generate because the wavelengths are typically measured in kilometers, for instance at 30 Hz you need a wavelength of 10,000 km, see Wikipedia:Radio wave. You can't just use an antenna kilometers in scale.

There are two main ways of doing this, using natural background radiation from various sources such as lightning (rare on Mars) diurnal changes in ionosphere heating, and solar wind.

The other method is "time‐domain electromagnetic" methods. A good paper about all this is this one:[1]

The way this works is that a pure sine wave is transmitted and then a broad spectrum of frequencies is generated when the signal is switched off. This generates a secondary circular electrical current that diffuses into the ground at an angle of 47 degrees expanding like a smoke ring as it descends. Described in another paper as:[2]]

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"The EM primary field diffuses downward as a plane wave because of the high air-surface impedittivity, which implies the electric field tolie in a horizontal plane. The eddy currents are horizontal and concentric below the transmitter loop and diffuse away through the mediumlike smoke rings."


Nobody has sent a detector of this type to Mars yet, but the Russians planned to do so with their Mars 94 mission. That never happened because of the fall of the USSR. Details here[3]

Grimm gives details about the Russian instrument as told by personal communication with E. Fainberg in 2000[1]

Nilton Renno droplets

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Summary: Nilton Renno and his team found that droplets of salty water can form in minutes when salt is thrown on top of ice in Mars surface conditions. This is something that could mean there are widespread tiny droplets of liquid that a microbe could live in on Mars. [4]

I asked him if his research means these droplets could be oxygenated. He said they haven't studied the time it would take for the brines to get oxygenated yet, but it's a good question.

Details

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This is the background here, from my astrobiology wiki again. This got a lot of media attention at the time. We don't need to go into this level of detail though I probably will in my expanded article, Droplets on its landing legs

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In 2008 through to 2009, droplets were observed on the landing legs of Phoenix. Unfortunately, it wasn't equipped to analyse them in that location. However, the leading theory is that these were droplets of salty water.[5] They were observed to grow, darken and coalesce[6], and then disappear, presumably as a result of falling off the legs. In December 2013, Nilton Renno[7] and his team using the Michigan Mars Environmental Chamber were able to simulate the conditions at its landing site and the droplets[8]. They formed salty brines within minutes when salt overlaid ice, with the salt, especially perchlorates, acting as an "antifreeze"[9]. The team concluded that suitable conditions for brine droplets may be widespread in the polar regions[4][10]. The Phoenix droplets may have formed on mixtures of salt and ice that were thrown up onto its legs when it landed. [4][10]. The Michegan Mars simulation chamber was developed to study the possibility of brines forming in Mars surface conditions


Mohmann model

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Summary: This doesn't get much media attention, so it was a bit of a technical question to ask him this. It is a way that fresh water can form beneath a thin layer of ice on Mars even if surface conditions are extremely cold, -56 C. Normally fresh water would boil instantly over most of Mars and be near boiling even at the depths of the Hellas Basin. But if covered with a thin layer of clear ice it is stable and in Antarctica then fresh water does form beneath clear ice because the heat is trapped by the solid state version of the greenhouse effect.

I asked him if oxygen could get into this water. He said that it might be possible through radioactivity in rocks breaking apart the hydrogen and oxygen in the ice, so leaving oxygen rich ice. He hasn't modeled this.

Details

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It's a bit technical to ask that question, I have a special personal interest in this model and wanted it for my own article on the topic. For some resaon it hasn't had much media attention but it gives a way to have fresh water within a few tens of centimeters of the Martian surface in polar regions, by a process similar to one that occurs in Antarctica.

Vlada was saying that it is possible oxygen gets into this water via ionizing radiation from radioactive elements in the rocks breaking up hydrogen from oxygen in the water ice. But they haven't modeled this yet.

If you want to do a shorter version of the interview and leave this question and answer out, okay by me. I can do the full interview in my astrobiology wiki. Indeed I have already uploaded it there, but marked it as NOINDEX so as not to scoop Wikinews:

This is how I summarize it in my astrobiology wiki:

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Möhlmann uses a solid state greenhouse effect in his model with translucent ice or snow-ice packs, rather than dry ice as a solid state greenhouse layer.[11]
Blue wall of an Iceberg on Jökulsárlón, Iceland. On the Earth, Blue ice like this forms as a result of air bubbles squeezed out of glacier ice. This has the right optical and thermal properties to act as a solid state greenhouse, trapping a layer of liquid water that forms 0.1 to 1 meters below the surface. In Möhlmann's model, if ice with similar optical and thermal properties forms on Mars, it could form a layer of liquid water centimeters to decimeters thick, which would form a few cm below the surface.
In his model, first the ice forms a translucent layer - then as summer approaches, the solid state greenhouse effect raises the temperature of a layer below the surface to 0 °C, so melting it. This is a process familiar on the Earth for instance in Antarctica. On Earth, in similar conditions, the surface ice remains frozen, but a layer of liquid water forms from 0.1 to 1 meters below the surface. It forms preferentially in "blue ice".[12]
  1. 1.0 1.1 Grimm, R.E., 2002. Low‐frequency electromagnetic exploration for groundwater on Mars. Journal of Geophysical Research: Planets, 107(E2).
  2. Filippini, R., Ottonello, C., Pagnan, S. and Tacconi, G., 2003. TDEM for Martian in situ resource prospecting missions. Annals of Geophysics, 46(3).
  3. The Future That Never Came: Mars 94 by Drew LePage
  4. 4.0 4.1 4.2 Liquid Water from Ice and Salt on Mars, Aaron L. Gronstal -Astrobiology Magazine (NASA), Jul 3, 2014
  5. First liquid water may have been spotted on Mars, New Scientist, February 2009 by David Shiga
  6. Staff writers, "The Salty Tears Of Phoenix Show Liquid Water On Mars", Mars Daily, Ann Arbor MI (SPX) Mar 19, 2009
  7. Nilton Renno - Faculty page, Mitchigen State University - Honors, Awards and Accomplishments, and Publications, etc
  8. https://www.researchgate.net/publication/283504377_The_Michigan_Mars_Environmental_Chamber_Preliminary_Results_and_Capabilities
  9. Gough, R.V.; Chevrier, V.F.; Tolbert, M.A. (2014). "Formation of aqueous solutions on Mars via deliquescence of chloride–perchlorate binary mixtures". Earth and Planetary Science Letters 393: 73–82. doi:10.1016/j.epsl.2014.02.002. ISSN 0012-821X. Bibcode2014E&PSL.393...73G. http://comp.uark.edu/~vchevrie/sub/papers/Gough%20-%202014%20-%20EPSL%20-%20perchlorate%20chloride%20mixture%20deliquescence.pdf. 
  10. 10.0 10.1 Fischer, E., Martínez, G.M., Elliott, H.M. and Rennó, N.O., 2014. Experimental evidence for the formation of liquid saline water on Mars. Geophysical research letters, 41(13), pp.4456-4462.
  11. Möhlmann, Diedrich T.F. (2010). "Temporary liquid water in upper snow/ice sub-surfaces on Mars?". Icarus 207 (1): 140–148. doi:10.1016/j.icarus.2009.11.013. ISSN 0019-1035. Bibcode2010Icar..207..140M. http://www.sciencedirect.com/science/article/pii/S0019103509004539. 
  12. Nl, K., and T. SAND. "Melting, runoff and the formation of frozen lakes in a mixed snow and blue-ice field in Dronning Maud Land, Antarctica.", Journal of Glaciology, T'ol. 42, .\"0.141, 1996