The detection of methane establishes the subsurface of Mars as a hydrocarbon province... Methane gas and hydrate deposits may occur in the subsurface at shallow depths on the order of ~15-30 m. Shallow methane gas deposits could constitute the most important near-term in-situ resource. Utilizing the natural resources of Mars could significantly reduce the cost of human exploration when compared with what would be required if these same resources were transported from Earth. In fact, the availability of these natural resources may prove to be the critical factor that will enable the continued human exploration of the solar system.A new paradigm of a resource-rich Mars should now be considered the basis of the planning of future human exploration, whether on Mars or beyond -- turning Mars from a remote, dead-end destination to a self-sustaining outpost that can serve as a stepping stone to the outer Solar System.
The IdeaFrom “Methane Hydrate on Mars: A Resource-Rich Stepping Stone to the Outer Planets?”
Quote from: LMT on 12/22/2017 06:09 amThe IdeaFrom “Methane Hydrate on Mars: A Resource-Rich Stepping Stone to the Outer Planets?”Depending on the volumes involved this could be huge.Many mfg processes (metal smelting, glass and concrete production) are very energy intensive. a large supply of indigenous hydrocarbon fuel radically simplifies the ability of any settlement to expand. A key question would be wheather this is a continuous process or if its a finite reserve, but just the availability makes a very big change to what it takes to make ISRU viable.
Potentially huge, yes. Worth the prospecting effort, don't you think?
ScaleThe generative process could be dormant today; accumulation over geological time is the thing. Pure clathrate is ~13 wt% methane, so even a small deposit would be useful. 1 km3 of pure clathrate releases ~120 billion kg of methane, enough for ~500,000 fully-loaded ITS Mars launches.
Faster ProspectingSay we take seismic surveying as the baseline prospecting method. What methods could deliver faster results? Perhaps a remote sensing method could be applied. For example, radar can penetrate polar caps from orbit, revealing much internal detail:But can radar detect clathrate under ice? At least one such method has been suggested, but I haven't seen application. See "A combination of radar and thermal approaches to search for methane clathrate in the Martian subsurface".
OxygenDiscovery of a clathrate deposit would bring the question of oxygen production to the forefront. Every kg of methane reacts with 3.6 kg of oxygen, so efficient bulk O2 production would be needed. At Omaha Crater a subaqueous dome could be dedicated for that purpose: 2 million+ sunlit m3 would support a practical, industrial-scale algae O2 farm, suitable even at present efficiency. If such a large space weren't available, farm O2 output at that scale would call for improved conversion efficiency, volumetrically at least 2 orders of magnitude above present algae-farm efficiency. One potential improvement under study: "Magnetic treatment of microalgae for enhanced product formation".
Where did it come from in the first place? What was the geological process that sequestered it? If no explanation can be devised, the likelyhood goes down, in my view.
Before getting too excited about this, I think there needs to be a good chance that these exist at scale. Prospecting is part of it (required) but another part is an explanation of how this methane was sequestered. Where did it come from in the first place? What was the geological process that sequestered it? If no explanation can be devised, the likelyhood goes down, in my view.Producing O2 with algae kind of begs the question of what to do with all the algae produced? It seems imbalanced... Might be better to break down CO2 and dump the solid carbon.This search might find more articles that substantiate the venting, if not the clathrates.https://www.google.com/search?q=mars+methane+vent+plume&ie=utf-8&oe=utf-8
IIRC SX are talking about using the sort of systems developed for the ISS for O2 production, using CO2 and water to get Methane and O2. With a ready supply of Methane I guess you could skip most of the process and go with water electrolysis, logically starting from the ice that held the Methane to begin with.
the H20/CO2 economy
Quote from: john smith 19 on 12/27/2017 08:02 amIIRC SX are talking about using the sort of systems developed for the ISS for O2 production, using CO2 and water to get Methane and O2. With a ready supply of Methane I guess you could skip most of the process and go with water electrolysis, logically starting from the ice that held the Methane to begin with.Reactor vaporization would give you water vapor for electrolysis, yes. However electrolysis itself is an energy hog, taking ~16 million Joules for every liter of water dissociated.
Quote from: LMTReactor vaporization would give you water vapor for electrolysis, yes. However electrolysis itself is an energy hog, taking ~16 million Joules for every liter of water dissociated.Catalytic Conversion of CO2 to O2Polar CO2 can be obtained in solid form, in winter up north, year-round down south, requiring no energy for compression. That could be a starting point for efficient conversion to O2. What are presently the most efficient catalytic methods for conversion of CO2 to O2? One example: A Study on CO2 Decomposition to CO and O2 by the Combination of Catalysis and Dielectric-Barrier Discharges at Low Temperatures and Ambient PressureParameters: specific input energy (SIE) of 55.2 kJ/L and low temperatures (<115 °C)
Reactor vaporization would give you water vapor for electrolysis, yes. However electrolysis itself is an energy hog, taking ~16 million Joules for every liter of water dissociated.
Hydrogen should be quite valuable on Mars.
Why not use the obvious Martian oxidizer, perchlorates?
Quote from: Joseph Peterson on 03/01/2018 05:55 amWhy not use the obvious Martian oxidizer, perchlorates?You could decompose perchlorates for additional oxygen, yes. Magnesium perchlorate is common, so it's one possible ice cap contaminant. In-cap application: Magnesium perchlorate decomposes > 300 C, so you'd need to redirect some HTSE heat (850 C) down into the chamber melt to obtain that oxygen. That pulls heat away from HTSE electrolytic oxygen production, increasing electrolytic power requirement. However if perchlorate concentration were high in the melt, perhaps net efficiency would improve, as perchlorate decomposition requires no electrical power itself.Do you want to try an estimate of the break-even, using HTSE power and heat? Refs.Ming, D. W., Morris, R. V., Niles, B., Lauer, H. V., Archer, P. D., Sutter, B., ... & Golden, D. C. (2009). Combustion of organic molecules by the thermal decomposition of perchlorate salts: Implications for organics at the Mars Phoenix Scout Landing Site.Suk Kim, J., McKellar, M., Bragg-Sitton, S. M., & Boardman, R. D. (2016). Status on the Component Models Developed in the Modelica Framework: High-Temperature Steam Electrolysis Plant & Gas Turbine Power Plant (No. INL/EXT--16-40305). Idaho National Lab.(INL), Idaho Falls, ID (United States).
although effort is needed for remote sensing, and prospecting, it is at least a consideration for even the first landings... easy access to CH4 early in Mars settlement would be a great step forward, even with the lack of oxygen you have discussed upthread.