Every school child can tell you these days that Mars is red because it’s rusty. The silicate rock of the martian crust and regolith is very rich in iron oxide. Now Australian researchers at CSIRO and Swinburn University claim they know how to break that iron loose.
In-situ Resource Utilization (IRSU) is a big deal in space exploration, with good reason. Every kilogram of resources you get on site is one you don’t have to fight the tyranny of the rocket equation for. Iron might not be something you’d ever be able to haul from Earth to the next planet over, but when you can make it on site? You can build like a Victoria is still queen and it’s time to flex on the French.
The key to the process seems to be simple pyrolysis: they describe putting dirt that is geochemically analogous to martian regolith into a furnace, and heating to 1000 °C under Martian atmospheric conditions to get iron metal. At 1400 °C, they were getting iron-silicon alloys– likely the stuff steelmakers call ferrosilicon, which isn’t something you’d build a crystal palace with.
It’s not clear how economical piling red dust into a thousand-degree furnace would be on Mars– that’s certainly not going to cut it on Earth– but compared to launch costs from Earth, it’s not unimaginable that martian dirt could be considered ore.
“It’s not clear how economical piling red dust into a thousand-degree furnace would be on Mars”
We are far from there yet, but in the end, unless you are doing asteroid mining in say the Xinglong (The Expanse), it’s likely more economical than launching Terran iron for those starter habitats.
Some sort of thermonuclear power source and a lightweight titanium furnace maybe? Oh, Canada (ISS) style extensible arms under machine learning control would be good there!
Launch that robot at Mars then come in later to (hopefully) a pile of pre-made ingots could be quite a “Satisfactory (game)” type starter habitat solution to get your crew out of the sun’s radiation.
(it’s fun to think of, anyway, even if very silly)
Perhaps we could save even more weight. Maybe a furnace could be built from Marian rock, either from small stones or better yet, hewn directly from a solid rock face, a bit like a lime kiln. We could start small, to bootstrap the process and then use the resources gathered to expand and refine the process. We can’t expect to hit the ground running if we are only going over there with the bear minimum. Who ever goes, they’ll be true pioneers.
A proof of concept display will be done remotely which makes the prefabbed route the only sane option. There may eventually be a more basic solution but initially it will be prefabbed. However, I doubt they will merely stop with making iron since a steel alloy would be much more useful.
First habitat will be the starship, if it goes there. 3 or 4 mm of stainless steel.
And then, we will need an economical way to do everything there… From rock wool to steel and electronics later on.
The goal is to create an independent world, even if exchanges exist.
…and you need to bring enough stuff with you to survive for 2 years. At least.
It’s a pipe dream at the moment. I’m sure it’ll happen in 20 years, which is good because then they can bring one of those new-fangled working-at-last fusion reactors with them.
The problem with ‘natural’ rock kilns is how disposable they are.
How much time/effort is each gram of processed iron worth?
ISRU is going to be super important, but not in the small scale.
We need to plan on putting multi-ton furnaces in place, which will require an entirely different launch infrastructure on Earth.
(Like, wildly different. Think linear rail launch assistance going up a mountain sized ramp…)
We can’t do that without long term planning, and it will either never be “profitable”, or only in the VERY long term. Which means we need leadership that can stomach government programs that don’t turn a profit in their pitifully short elected terms.
The whole ‘for profit’ private space industry is insane, and it doesn’t get us ground plebs anything.
If we are ever going to make real progress off this rock, it will have to be something we ALL pay for, and we do on principal.
It can’t be about prospecting.
It must be about the simple exploration.
Or you send up small likely self assembling robotic system that allows you to bootstrap the tech tree and build the larger industrial facilities required quickly but without having to actually bring the facility with you. In much the same way you can make your own lathe, and from that lathe any other machine tool with nothing but pretty basic hand tools and some sand casting – it takes a heck of alot longer than having somebody who has already done some of that work letting you use their existing machine to make bits of yours.
Much as that sounds nice I’m rather certain real progress will one day be made in space even if it just to make Musk or whomever inherits the title of wealthiest muppet by the time the technologies are ready even wealthier and more powerful.
Given the amount of radiation and the daily temperature extremes, living on the surface is a not a good option. However, this could be useful for constructing other things that we will need, if we can manage to bootstrap real automated manufacturing.
“starter habitat solution to get your crew out of the sun’s radiation” at 1/3g a lot of local regolith can be piled on a habitat. The air pressure alone at 1 atmosphere can support around 5 meters. With Victorian era cast iron structures?
Very funny guys, who swapped out the regolith simulant for Milo?
So, if we could forge lengths of circular section iron up there would they be Mars bars?
I’ll see myself out.
The audience Snickers.
…and Mars does reside within the Milky Way.
neat, but no one is going to mars
The chances of anything coming from Earth are million to one, they said…
Dun-dun-duuuuh!
Dun-dun-duuuuh!
Cue groovy bass rift…
Can we just send Elon?
Yeah, space is a LARP at this point. We’re stuck on this rock.
Sad but true. We should’ve given NASA a bunch of money and nukes back when they were cooking with gas. The current one is ngmi
I suspect you are wrong, as the way the world is going Mars is going to be the next great power flexing moon race most likely.
Though this time it might actually be happening at a time when our tech level can actually make use of the resources of the outer solar system and we’d want/need to exploit that resource to make up for the lack down here, or at least the lack down here on your side of the planet… Which makes Mars a viable jumping off point for the great powers to compete for effective ownership of the entire solarsystem – can’t do much from down the gravity well once your opponent can build in space effectively enough to drop rocks on you very cheaply.
If we can’t send stuff from Earth to Mars, then it’s going to take setllers on Mars hundreds of years to build a society that resembles the one on Earth. Maybe thousands of years.
Are we going to pump trillions of dollars into a colony on Mars? Or just a few billion dollars and then let them live and prosper?
A colony on Mars sounds nice, but if they can’t even make their own integrated circuits. They would only have two options: rely on us gifting them their IC’s, or buying them from us.
So, if we don’t want to gift them (it’s a colony after all, not a hobby), they’ll have to buy them from us, but buy them with what? What would they have on Mars that we would want to have?
Strip the romantics, and you’re left with reality. Reality is that Mars does not have anything that we don’t already have ourselves. There will not be trade between Earth and Mars. And if there is no trade, a Mars colony will not prosper.
The moon, however, DOES have something we need: a significantly lower gravity than Earth. We need that to be able to explore the further reaches of our solar system. A colony on the moon is much more realistic. People want to pay for exploration.
There’s a lot of radioactive sand on Mars. Sand we just start to lack on Earth to build more concrete kilometer high tower to pack more humans so they can shoot themselves and tell others how they are happy to be so rich while being so desperately empty inside. Look how I’m rich in my Mars concrete highest tower in Dubaï.
Don’t worry, as long as there are crude wealthy people, there will be moral-less vendors to exploit them.
So what? Not the point at all, people go to Mars quite probably with no intention of actually building a self sufficient society – can’t have the colony turning on you…
My point is the great powers that are busy competing with each other DON’T have everything themselves – or at least not large enough quantities of everything. So the initial ‘exploration’ of Mars will be done for political grandstanding, if enough tech and resources exist to start making useful materials, even if its mostly just refined materials sent ‘home’ to be worked on with some high complexity industry products sent out to make it possible.
You know, the idea that the future always has to be bigger and better than the past is not strictly true
Yeah, it’s dick-waving contest V2. V1 was “first to Moon” with USA vs the Russian commies, now it’s USA vs the Chinese commies.
The Chinese will get hands on some Mars rocks 2030-ish, but no-one is sending people any time soon. The USA hasn’t even a plan for how to bring their rocks back at the moment, but Sean Duffy was being very loud about how they’re going to win this race as well. Good luck with that dude.
You are talking about space tech that is 1000 years in the future.
The last 50 years of leadership has shown that they don’t care about much other than enriching themselves during the next half-decade.
We are never getting back to Luna, let alone Mars, if it needs to be profitable in the next quarter.
Our current ‘private’ space industry is more about the pageantry to fleece investors than any actual ‘space’ exploration.
“Swinburne University” would be the usual spelling.
Rather than heat everything including impurities, why not use an electromagnet to extract pure iron which can then be smelted?
What am I missing?
Oxides are a bond of iron, not pure iron. So you need heat to break the bond
Sure. But in the dirt not all of it is iron oxide right? So you can either heat dirt + iron oxide or just heat iron oxide…
Most iron oxides seem to have “superparamagnetism” aka they are only magnetic when in an external magnetic field.
Seems like a very simple and prudent purification step
15-20% iron oxide (Fe2O3), 40-50% silicon dioxide (SiO2), 7-18% aluminum oxide (Al2O3)
The reduction temperatures of each of these escalate in that order. This is why at 1000°C they get iron metal and at 1400 °C, they were getting iron-silicon alloys.
Ahhh, taking advantage of the different melting points. Got it.
Iron oxide is not magnetic, you need to reduce it first.
Mars doesn’t get a whole lot of sunlight, so energy will be at a premium. You could use the product and waste to pre-heat the fresh material. Maybe we could build an efficient high-temperature heat pump to bring the energy requirement down further.
Mars gets quite a bit of sunlight, around 12 hours a day. The intensity is lower than the earth sure, by about 50%. Big deal. Youll just need twice as many panels.
Twice as many panels is twice as many rocket flights to Mars. Is twice as many billions of dollars. And what does Earth get back for that?
Reality revolves around economics. That is the real reason why we are not on Mars yet. It’s not economical, we get nothing out of it other than a bit of interesting but otherwise useless knowledge, and maybe some innovations that we can use for more than just a spacecraft that can fly to Mars and back.
ideally,
solar panels made ON mars would be used to power mars.
The ONLY advantage to a mars colony is ensuring the survival of humanity in the event of major cataclysmal event on earth.
Uhh Most iron oxides have “superparamagnetism” aka they are only magnetic when in an external magnetic field. So yeah.
So yes that could be used, but as someone else pointed out it isn’t needed when taking advantage of different melting points.
Quite a while ago I saw an image of a Mars lander that had drilled a hole for a sample, and what struck me as noticeable was that the red layer was very thin, and there was not much dust to go through, and it perplexed me since there are these constant dust storms and you would think there would be a thick layer of dust (there is plenty of red dust on the landers after a while) and that the dust would in general be red, but from that image that seemed not to be the case.
I’m still wondering how to explain that.
Simple, you land on rock, not sand dunes.
Mars has plenty of sand dunes, they work pretty much the same way as they do on Earth.
Also most of the samples they take are from outcrops or boulders, not from the ground. Plenty of dust on the ground though, as seen from the rover tracks or other missions where they’ve scooped it up.
Well, the big difference with what is considered an “ore” on Earth is the economics of extracting the target mineral/element from it. Common “dirt” contains many valuable minerals and elements, but in such low concentrations that it doesn’t make sense presently to extract it, from an energy-budget standpoint. The same could be said of seawater.
It may be that the necessities of ISRU could lower that bar for what is a “useful” concentration. For instance, perhaps a process like sintering could be used to form simple structural elements for nascent shelters. With the low atmospheric pressure and gravity, even extremely high winds don’t deliver that much energy so erosion isn’t much of an issue. And there is no hydrological erosion. An amalgam of sintered regolith could be a viable option. Further processing could yield better materials for other purposes.
Well, as Earth has an unusually large iron core compared to the neighbours (Venus has a large one too, according to observations) , and an active tectonic surface renewal operation going, Earth has a lot more iron available at or near the surface than any other planet in the Solar System. Mars, having no perceivable tectonics, will be very iron poor at the crust. Earth and Venus have large cores due to large collisions in the early early Solar System (why Earth has such a large moon, and why Venus doesn’t spin on it’s axis the way most of the planets do).
Sintering is ok for habitats and so on, but at some point you’re going to need the actual pure metals. Same idea has been proposed for the Moon, focused sunlight to melt the dust into bricks.
Welding on the Moon would be novel, no atmosphere to cause problems.
Baby steps :)
Yeah, lot & lots & lots & lots of little baby steps.
Until someone figures out a way to drop a fusion reactor on Mars, nothing is going to happen.
Just use the xbox towel trick. Dump atmostpheric thinners and reflectors until it gets super hot on mars and all of the iron reflows into a harvestable shell. Ta Da!