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Isn't there plenty of oxygen which could be much more simply burned out of mars rocks? Place is covered with fine dust that's almost entirely metal oxides. I'm

Isn't there plenty of oxygen which could be much more simply burned out of mars rocks? Place is covered with fine dust that's almost entirely metal oxides. I'm thinking concentrated solar to liberate the oxygen and produce a nice metal building material that could be refined to base metals for all sorts of things.

ortusdux 4y ago
I've always thought this was the obvious choice. I wonder what the logistical issues are. As a bonus, you get pure iron as a byproduct, which would be worth it's weight in gold as a building and additive manufacturing resource.
- colechristensen 4y ago
  If you just roast common Martian soil you don't just get iron but many metals mixed together (the three mars landers tested and got pretty similar results at a high level)
nickpinkston 4y ago
That's my intuition too, though given's gene-h's citation [1] in this thread, there may be an interesting analogy between water evaporation and reverse osmosis, as the proposed tech creates a plasma and the oxygen diffuses through a membrane (like osmosis tech). We know that reverse osmosis is the more efficient tech compare to evap, so who knows. [1] https://aip.scitation.org/doi/10.1063/5.0098011 https://aip.scitation.org/doi/10.1063/5.0098011
hinkley 4y ago
On earth a great deal of life's variety happens at the boundaries, such as in tidal zones and estuaries. There are no oceans on Mars but there is also very little atmosphere. I suspect we will want to engineer our oxygen producing equipment to make estuaries and tidal zones for atmosphere, where there is either a steady stream of atmosphere, or daily pulses that push life to adapting to temporary deficits and surpluses of resources. Later on that could be accomplished just by routing the exhaust down into the canyons, but early on that may have to go through greenhouses, which either vent above a certain pressure or aren't quite hermetically sealed.
stereoradonc 4y ago
Imagine if all that were Gold :-)
- martin_a 4y ago
  Now you're thinking like a human. The council of extraterrestrial life has acknowledged that.
adrian_b 4y ago
The binding energy of the carbon dioxide taken from the Martian atmosphere is much less than the binding energy of the metal oxides from the Martian rocks. So the thermal decomposition of the rocks will require much more energy. As you say, the thermal decomposition could be done directly with solar light, bypassing the conversion efficiency of the photovoltaic cells. That brings the energy requirements to similar values. Which would be the more efficient process would depend on details, e.g. the type of photovoltaic cells, the exact composition of the rocks whose decomposition is attempted, the usefulness of the byproducts, e.g. reduced carbon or reduced metals, and so on. When taking into account the byproducts, it is likely that both processes will be needed anyway.
7speter 4y ago
I think a big difference between Earth and Mars is that, because our planet is still geologically “alive” (it has a molten core and off gassing occurs on its own, the most easily observed example are volcanoes), the planet has been off gassing the needed molecules for life for millions, if not billions of years, and because of the nature of the molten iron core of our planet, we are able to hold these chemicals within our complex atmosphere without much artificial effort. While mars may have been geologically dynamic at one point, it either is drastically much less so now or pretty much dead. Terraforming by means of burning through the surface would have to be an ongoing thing process because not everything we’d burn would be beneficial for our understanding of life (us and the ecosystems we are used to on earth), but it would also be very hard to keep what we generate on Mars in an atmosphere. Could be wrong, though.

ortusdux 4y ago

I've always thought this was the obvious choice. I wonder what the logistical issues are. As a bonus, you get pure iron as a byproduct, which would be worth it's weight in gold as a building and additive manufacturing resource.

colechristensen 4y ago
If you just roast common Martian soil you don't just get iron but many metals mixed together (the three mars landers tested and got pretty similar results at a high level)

nickpinkston 4y ago

That's my intuition too, though given's gene-h's citation [1] in this thread, there may be an interesting analogy between water evaporation and reverse osmosis, as the proposed tech creates a plasma and the oxygen diffuses through a membrane (like osmosis tech). We know that reverse osmosis is the more efficient tech compare to evap, so who knows. [1] https://aip.scitation.org/doi/10.1063/5.0098011 https://aip.scitation.org/doi/10.1063/5.0098011

hinkley 4y ago

On earth a great deal of life's variety happens at the boundaries, such as in tidal zones and estuaries. There are no oceans on Mars but there is also very little atmosphere. I suspect we will want to engineer our oxygen producing equipment to make estuaries and tidal zones for atmosphere, where there is either a steady stream of atmosphere, or daily pulses that push life to adapting to temporary deficits and surpluses of resources. Later on that could be accomplished just by routing the exhaust down into the canyons, but early on that may have to go through greenhouses, which either vent above a certain pressure or aren't quite hermetically sealed.

stereoradonc 4y ago

Imagine if all that were Gold :-)

martin_a 4y ago
Now you're thinking like a human. The council of extraterrestrial life has acknowledged that.

adrian_b 4y ago

The binding energy of the carbon dioxide taken from the Martian atmosphere is much less than the binding energy of the metal oxides from the Martian rocks. So the thermal decomposition of the rocks will require much more energy. As you say, the thermal decomposition could be done directly with solar light, bypassing the conversion efficiency of the photovoltaic cells. That brings the energy requirements to similar values. Which would be the more efficient process would depend on details, e.g. the type of photovoltaic cells, the exact composition of the rocks whose decomposition is attempted, the usefulness of the byproducts, e.g. reduced carbon or reduced metals, and so on. When taking into account the byproducts, it is likely that both processes will be needed anyway.

7speter 4y ago

I think a big difference between Earth and Mars is that, because our planet is still geologically “alive” (it has a molten core and off gassing occurs on its own, the most easily observed example are volcanoes), the planet has been off gassing the needed molecules for life for millions, if not billions of years, and because of the nature of the molten iron core of our planet, we are able to hold these chemicals within our complex atmosphere without much artificial effort. While mars may have been geologically dynamic at one point, it either is drastically much less so now or pretty much dead. Terraforming by means of burning through the surface would have to be an ongoing thing process because not everything we’d burn would be beneficial for our understanding of life (us and the ecosystems we are used to on earth), but it would also be very hard to keep what we generate on Mars in an atmosphere. Could be wrong, though.