Mining is Secondary, At Best, For Space
This is mostly in response to this article which talks about mining in space and misses a lot of known engineering and science. Lets start with this:
It might be more surprising that, for the most part, they plan to leave all that metal alone, at least for the time being. What they seek first is something we have literal oceans of here on Earth: water. Water can support human life in space, and it can be split into hydrogen and oxygen, which, when burned together, make a nice rocket fuel. Experts foresee gas stations in the sky for servicing satellites or taking people much farther out. Water has been called the commodity of space.
This does hint to the most important pieces in space travel and migration. Metal ore does nothing for you if you don’t have food, air, and water. These things are incredibly expensive to export from Earth. However, it ignores, or doesn’t know about, research and engineering work that has been done and confirmed for decades.
Water, air, and with a few additional steps, are easily solved on Mars. Gas lamp era technology is all that is needed for this to extract and produce O2 and water from the martian atmosphere. We don’t need expensive and long term research into possible comets as a source — we have a confirmed source and have already built what is needed to reliably produce it. The equipment is simple, cheap, lightweight, and space efficient. This makes it an excellent export from Earth to get started. However, the most important aspect is that is is known and proven.
Orbital facilities are horrendously expensive, arguably prohibitively so. The shielding requirements are larger than anything else we’ve seriously considered. The sheer mass required to provide even reasonable protection from radiation for humans to live in space to do the mining and support operations is orders of magnitude larger than we have the know-how or launch capability for. This has secondary effects which are just as significant.
Due to a lack of ability to launch hundreds of tons of cargo into space in a single go, we would have to do it via on-orbit assembly. We don’t have significant experience doing this, which means more research and more decades of time spent. Sure, we pieced together the lego brick of the ISS, but that is far different than assembling an actual space ship that has to haul cargo to and from the asteroid belt. Then we have the propulsion requirements once it was in orbit. We’d have to launch, in a short window, about as much mass in fuel as we did in ship mass — assuming we also didn’t have to ship heavy amounts of orbital assembly infrastructure to go with it.
Which brings us to the next problem: going from Earth to asteroid belt or the moon and back is one of the most expensive things we consider. While it may seem counterintuitive, the fact is it takes more “delta-v”, more change in velocity, to go from Low Earth Orbit (LEO) to Earth’s moon than it does to go to Mars. To put it simply, Mars has something neither of the other two proposed destinations have: atmosphere.
Yes, it is thin. But it provides a massive advantage in that you can use it for “capture” and for landing. To put it simply, to go to the Moon you have to carry fuel to power rockets to slow yourself down. That means you have to carry even more fuel to push that extra fuel to slow you down to get into orbit (“capture”), then you have to use more fuel to control your descent to the surface. See the problem with that? Can we do it? Clearly. However, it is expensive. With an asteroid it is even higher due to the lack of an appreciable gravity well to provide any capture assistance.
Mars, however, has that thin atmosphere which we can dip into to slow us down. We can also use it to slow our descent — even using parachutes. This means far less mass needed for fuel (and for capture rocketry) which in turn leads to either enabling smaller and less costly shipments, or more usable cargo for that level of launch mass. While the atmosphere of Mars is thin, there is much more of it than we can ship from Earth. This brings us to the next advantage: shielding.
Mars’ atmosphere, while thin, still provides significant radiation protection. But the benefit doesn’t stop there: Mars itself is a rather large radiation shield. Much larger than we can export for free-space mining operations.
JPL wasn’t sure what tools it would require to mine. Scientists know that Mars’ soil, or “regolith,” contains water in its minerals that is released when heated. That can be done with a hollow heated drill, or the regolith can be dug up with shovels or a tunnel-boring machine and then transported to a plant in trucks or a conveyor belt.
This is a result of undue focus. Why try to figure out how to extract water from the ground when we can easily produce it from the air? When I see this type of thing it tells me that the people in charge are looking for money to create a solution in search of a problem. Water, air, and fuel from the martian atmosphere is a solved problem. It has been solved for decades. If you are in the industry and don’t know this you aren’t doing your research on what has gone before. Indeed, that research has continued, and improved. By the way, In-Situ Resource Usage is so-called because it isn’t a euphemism for mining, but using local resources — such as the atmosphere, or the ground directly for building materials.
Now let us return the mining aspect.
He plans to start figuring out how to anchor spacecrafts to asteroids.
This illustrates another advantage of Mars: we don’t need to figure out how to do that kind of thing. Mars has enough gravity (~40% that of Earth) that we don’t need to figure out how to mine in free space, we don’t need to figure out how to anchor to that which we are breaking up, we don’t need to figure out how to transport, and do all the things that we take for granted in mining in a gravity well. Because we’d be mining in a gravity well.
Now you may be wondering what the point of going to another gravity well is. After all, isn’t the gravity well the problem? Not really. Getting from the surface of Mars to Earth’s moon (Luna) takes less energy than going from Florida to Luna. The difference is astounding, but makes sense when you apply thought to it.
First, the well is only ~40% as “deep”. But there are secondary effects that compound the benefit. Due to the lower requirements we have lower thrust requirements but also lower dry mass “ie. just the ship” mass requirements — the forces are smaller. Second, the lower mass and shallower well means less fuel is required for launch and you can use locally produced fuel that wouldn’t be as efficient launching from Earth. This means per unit of ship mass or fuel, you can put more cargo mass at your destination launched from Mars than from Earth.
Combine that with the above advantages and the cost to go to Mars, establish a colony, an then branch out from there outweigh everything else we know. But what about mining on Mars? First we need to realize that most of what we’d need to expand human space on Mars we don’t need ore mining for. We have plastics, which we can also make using lightweight feedstock from Earth and combining it with the atmosphere of Mars. The first priority in long term space presence is food, air, and water. The second is expansion space. Again, there is nowhere else in the solar system that carries the advantages to the level of Mars.
Indeed, bootstrapping from Mars means you can build what one might call an interplanetary highway. I won’t go into detail here as I already have written about it here. You won’t get that from Earth based masses. There is nothing else we know of that actually moves decisively in the direction of cheaper space travel and transport. The tether system I wrote about does precisely that. This is the next major flaw in “free-space mining first” concepts: they ignore the reality, and costs, of transporting all of that mass.
However, a Martian foothold has such tremendous advantages in that arena that nothing else, short of “mass doesn’t matter anymore teleportation” drive fantasies, can compare to.
Now let us revisit the Martian gravity well benefit with regrds to Earth based mining company and know-how. Specifically, lets talk about the miners and the training. Which is easier: training a miner on mining equipment that works on Earth while possibly wearing a Mars surface suit, or training them to operate in zero-g? Leveraging existing capability and techniques further reduces the cost by expanding the pool of potential miners and operations people. Putting them on Mars is less risky, and cheaper, than free-space meaning more people would be willing to do it. This brings us back to belt mining and Mars’ advantages.
The asteroids will have raw ore, plus other bits and bobs. You will either need to transport all the excess material or refine to smaller space and less shipped mass. Doing that in free space is a complete unknown. So you’d either have to spend yet more money and decades of research and orbital practice (where you ship the raw material up, further increasing its cost) to do that in situ, or you ship the bulk back — more energy and thus more cost.
Alternatively, you can spend far less and ship it to Mars’ surface, where we can use our known techniques to reduce it to a more shippable form; plus you could use it on Mars itself. Yes, the cost of this sequence is lower than the cost of doing it in situ, and lower than shipping the raw material to Earth for reprocessing.
She says the greatest difficulty in planning for Mars is the lack of information, since you can’t easily drill or pick up rocks to do surveys like you can on Earth. “So there’s a lot of science work that still needs to happen,” she says.
Exactly, and the most effecient and effective route to do that is to put a colony on Mars. The you can go out and pick up rocks, do surveys, drill, and so forth. Plus, that means it is even more difficult to do for asteroids.
We understand the moon better than the other options, and it’s close.
The first half is incorrect, the second is a red herring. As I’ve noted, and is known by anyone looking at the mechanics, it may be closer distance-wise, but it costs significantly more energy-wise, which means it costs more in terms of money and time to research. Luna’s gravity well isn’t enough to be directly applicable in terms of mining physics and carries every disadvantage of being in free-space. Luna isn’t a waypoint or a source of raw materials, it is a final destination and consumer of exported materials.
We understand Mars better than we understand Luna. Mars has enough gravity to work normally in. It has enough atmosphere that we can operate in it with small modifcations to existing technology and equipment. It has resources we known how to harvest and use. We’ve already proven we can produce plenty of air, water, and fuel on Mars — while nobody has done the same for Luna. We know we can produce food on Mars with minimal shielding and/or power compared to Luna (we grow food in similar and lower light levels on Earth). The conjecture about doing this on Luna is just that: conjecture.
If you’re going to say someone is considering the economics of off-earth mining, then they need to be looking at everything required to establish the infrastructure. They need to be considering transport, life support, protection, expansion, time, and leverage. I don’t see that being observed anywhere in the article. Perhaps because those being referenced aren’t doing it. They show no evidence of it. Anyone who looks at the whole picture can’t come to the conclusion that the economics favor free space mining, or lunar mining, for a market that doesn’t exist. Less gravity is not “easier”, it is the currently the inverse: we know how to mine in a gravity well and we have the technology.
Here is a good way to really get a good understanding of an “off earth mining company”: look at how they talk about — if they do — transport. Are they sizing their payloads, equipment, supplies, etc. to fit current Earth sourced rocketry? If not, they’re probably a money sink. If not, are they also designing and researching larger rockets to fit their plans? If not, they are definitely a money sink and probably a waste of time.
The numbers are 15x higher to go to Ceres than to Mars. And that is just getting there. So consider this: company A is going to Mars to mine, company B is going to an asteroid in the belt. Company B has 15x the cost, just to get there, of Company A. Who’s product will be cheaper, or will make more money? Assuming the costs of on-site harvesting and returning the cargo to Earth were the same, which company would you invest all of your money in?
Now add into the calculation that Company B still needs to figure out how to mine the asteroid so they are about 15–20 years further out from a return. Since we know the costs for onsite harvesting are higher in free space than on Mars, and that the return trip is cheaper from Mars than from the Belt, which company will be better situated economically? Which is the better investment? Which brings us to the next quote.
It (sic) CEO, Dale Tietz, said Dubai’s Sheikh Mohammed had planned to invest $18 billion but recently dropped out.
That amout of money would establish a solid Martian colony. Granted, that doesn’t solve the “problem” of there being no market for the alleged water from lunar ice “supply”, given that Mars can make its own water, and air, and fuel. That does, however, seem rather poignant. Mars doesn’t need it. What Mars needs in that context is hydrogen — which is pretty light and can be highly leveraged — which can also be used to bootstrap a martian plastics industry.
Only Mars has the mass-critical resources needed to be off-earth, and in a form and situation we already know how to harvest and process. What a budding martian colony needs to import is predominantly lightweight, value-dense materials and goods such as high tech electronics, chemicals, etc..
Mining of the belt will take place, if economically driven, from Mars, not Earth. For a roughly 50 ton cargo freighter you are looking at dry ship mass of around 95 tons.
From Earth that will require about 1200 tons of fuel (Meth/Ox since LoX and H do not store well in space) for the transit propellant alone. In order to put that mass into orbit for assembly, you’re looking at a total launch-from-Earth-surface mass of nearly 110,000 tons including the propellant.
To do the exact same thing from Mars’ surface requires only a total of about 2000 tons. With a difference factor of over 50x, Mars enjoys a tremendous advantage. Now consider the two companies scenario earlier. Obviously, Company A was the better bet at a differential factor of 15 when it was just the cost to get there. Throwing in more of it brings it to over 50 times more expensive.
Now to note, these do not include food, air, and water for the crew for their mining stay since we don’t know how long they will have to stay. An added benefit of illustrating it that way is that even if you had perfect robots, it doesn’t change the equation enough to matter. But clearly, even just getting there, hitching some cargo into the hold for terrestrial processing, and coming back is seriously more expensive from Earth than Mars. You can build out the Mars settlement and facilities for less than the cost of the first Earth-based freighter mission. That said, since the trip from Mars to the belt is much shorter, crew requirements will be lower for Martian mining freighters than Earth based ones. Now let us step away from the hard science and numbers to look more broadly.
A proper understanding of the future of human exploration and expansion requires a grounding in the history of it. Nowhere in our history do we have the scenario of remote mining ever panning out. We always build living space and use local resources to support the humans where we could do mining. We didn’t know where the ore veins and deposits were when America “went west” either — we moved there then looked for them. We didn’t move to the desert first, but instead we moved to where the water was and grew out from there. Luna and free space asterids are barren tundra at the top of very steep and tall mountains, whereas Mars is a gentle fertile plain up the hill by comparison.
We didn’t send mining crews from Boston to Montana and expect them to bring back their cargo in the same vehicle that took them there, and without setting up local living conditions. We won’t sucessfully do it today, either. Robots don’t change that — as anyone who has worked with production robots, and isn’t seeking funding, can tell you.
“Once we establish the robots,” he says, “in the next 10, 15 years, mines will have less people. After 15, 20 years, mines will have no people.”
Which is something we’ve been hearing for decades. The perfect robot is like fusion: always another $50Bn and 15–20 years away. And, like fusion, the perfect robots require something we don’t know if we can actually make: genuine AI. At best, that AI will have to learn the way humans do. At a minimum we’d need to have the knowledge of how to perform mining operations in space to program into them. Guess what we don’t have. Creative, intelligent, flexible AI driven robots are a modern snake oil.
I get it: talking about mining asteroids is sexy. But it isn’t practical, efficient, or even something we yet know how to do. Sure, saying there are XX million tons of <insert ore> in asteroids sounds amazing, and like a prime target. However, the physics, economics, and historical path of expansion do not support it. It will happen eventually, but it won’t be a successful next step for humanity’s never ending drive to expand and grow. Mars is the key to mankind’s quest for spacefaring.