Your math is off. 50,000 kg * $30,000/kg = $1.5 billion.
Also, as far as I know Starship should be able to land with ~100 t payload. It may require launching without a payload, though. Either way, the launch costs will be negligible compared to that quantity of platinum (or gold).
Oh for sure. But remember the economics here - A starship flight may eventually only cost a couple of million dollars. It might even make economic sense to fly dedicated missions up to the depot just to bring back gold and platinum.
You know, when we talk about how to do things in the future we always talk about it in sort of ‘clean room’ terms in the sense of debating the cheapest, best technology, etc. But that’s not really the way things evolve. We never account for the complexity of how markets actually develop.
For example, here’s a scenario that could lead to a ‘spaceship only’ transportation system - a company like SpaceX builds 10 starships per year (their planned rate, btw). These things are reusable, so after two years they have an inventory of 20. After three years, 30. If each one is good for 100 flights, they now have a capacity for 1000 flights per year while maintaining a fleet of 30. Maybe there is an initial market for that, but other entrants plus an eventual downturn in demand causes a large glut of rockets. By now (say, 10-15 years from now) the reusable rocket business is pretty reliable, and rocket flights are routine. Every day sees the launch of several rockets around the world.
Now a space mining company, which used a cheap starship flight to send a 100 ton miner to a metal rich asteroid, contemplates how to exploit its find. Bringing it back too fast will simply crater the market. It has to be brought back slowly enough to allow demand for the now-cheaper metal to grow as new uses are found.
There are other mining companies exploiting other asteroids, and they have the same problem. So they collectively realize that an answer is to restrict supply to Earth, much like OPEC. And the easiest way to do that is to start a lobbying campaign to make ‘direct drop’ return of cargo illegal, siting dangers to wildlife and people. Then you get laws passed against it, essentially giving the rocket companies a monopoly on metal transportation from orbit.
Sure, it’s more expensive than it needed to be, but in this case that’s a feature. Now space metal is being fed into the economy at a nice controlled rate designed to optimize profit as the price inevitably declines.
Of course, I could make up an equally plausible scenario for a future in which rockets are forbidden to bring back such cargo. For instance, if current cartels and mining interests put massive pressure on politicians to advocate a ‘Space materials are for space’ campaign, making it illegal to use space-based minerals on Earth. Too much disruption to existing markets. A real world example would be deBeers and other existing diamond mining concerns lobbying to make lab-grown diamonds carry an etched marking identifying them as ‘not authentic’.
It’s like the typical debates we have regarding the best place to colonize. We talk about Mar’s better gravity than the moon, the moon is closer, Mars has an atmosphere and could one day be terraformed, whatever. In fact, there is only one criterion for the best place to colonize first: The place where there is profit to be made doing so. Nothing else matters. Until we identify a source of profit, we won’t be colonizing anything in space. The math doesn’t work.
The heat of re-entry is essentially the re=entry vehicle compressing the air ahead of it. Compress a gas, it gets hot. Compress it with a projectile going 17,000mph and it gets really hot. Thanks to Newton’s laws, conservation of energy means the velocity of the mass is converted into heat, and the vehicle’s speed - it’s kinetic energy - is translated into heat. That’s why anything with a high amount of air resistance - and empty can - will create less heat. The kinetic energy of a ton of nickel spread over 20 square meters will be the same as a blob a meter square - but will compress 20 times as much air 9approximately) and so the same energy over a wider area means less temperature increase overall.
(I would consider a shape like a globe simply because then aerodynamics doesn’t matter - but if there’s a way to make it autorotate to change the face presented to the heat of re-entry - a spinning globe - even better. Maybe we should drop volleys of giant nickel wiffle-balls into Death Valley.
Which deposits of Helium-3 will be worth extracting also seems to depend on the future demand for it (lots of fusion? MRIs? Cryogenics?) and how cheaply it can be produced in terrestrial nuclear reactors.
According to Wikipedia, the baseline price was historically around $100/l (ie $800/gram) and shot up to a peak of $2000/L (ie $16000/g) in 2008 before going down, since the demand has fallen from 70000 litres/year by US industry alone down to 6000 liters/year.
See this page by a JPL physicist: “Rule 2: There is no commodity resource in space that could be sold profitably on Earth”: Unpopular opinions in space – Casey Handmer's blog
I’m glad the moon has not devolved into a robotic mining colony like some people were predicting would already be the case by 2015 or 2020 or whenever.
Spinning is bad for hitting the target zone. This is a curve ball on a grand scale.
The shape of the Mercury->Apollo capsules was really good. Highly stable, only the bottom needed shielding, predictable landing spot. Gordo nailed his landing the best of the Mercury flights. Despite losing a bunch of automatic attitude control and such and having to fire the retros on Glenn’s count. Landed within 4 miles of the recovery ship. (Which is not the actual target but is a good measure of accuracy.)
Figure a 20 mile radius for unmanned, heavy blobs of metal. That’s a pretty big area. If was a sphere, figure at least a 50 mile radius. And you have to have good tracking to figure out where it landed. You don’t want to search an area that big. Radio tracking on a hot, rotating sphere coming out of the upper atmosphere isn’t easy. It’s trivial with a cone shape.
Why?
Same reason as Antarctica. It is not from an economic consideration.
Well, I’m not sure what your argument is for Antarctica, either If it’s that it’s pristine and should be left that way, why would you extend that to the moon? The moon is a lifeless rock. There’s nothing we could feasibly do to it that could be seen from Earth. There are no habitats to destroy.
If we don’t use the moon, it is just another of trillions of lifeless rocks in our galaxy. But if we use it to our advantage, it could one day be a source of pollution-free mining and manufacturing, could house millions of people, and be an easy jumping off point for further exploration.
Declaring our closest major space resource off-limits to human expansion for no reason other than that we aren’t currently there makes no sense.
“If a senior scientist says something is impossible, they’re probably wrong.”
–One of AE Clarke’s Laws.
The OP assumed the existence of technologies to push asteroids around and robotically mine them. I figured the existence of such technologies implies changed human societies, so why not use the Niven model? It’s essentially economic: what’s profitable will happen.
No, Belters don’t yet exist, and neither do fusion drives. I’ll not bet against either.
The question is - what would you find on the moon that is profitable, if you were to mine it? Water (and so Hydrogen and oxygen) would be of high value - once we have regular spaceflight beyond earth orbit and habitats. Metals? You’d have to find a serious motherlode of some very rare mineral to compete with Earth-based mining. Refining gold, right now, uses a lot of water (grind and pan on giant shake tables before smelting). While I don’t doubt the process could be automated and run remotely, presumably the same sort of tech might work to process the deep layers of silt in many terrestrial rivers where there were gold finds in the Good Old Days - and a lot cheaper. And… the trick is finding the motherlodes on the moon. Here we map the general geological strata often from samples and seismic blasts, then drill the interesting bits to get a 3-d map then more intensively where we think there is something. The last stage is usually enhanced by a rush of small prospectors staking out claims to hope theirs pays off a jackpot. The process and much of the geology would be far different on the moon.
And Rico has the best point - the energy to get an asteroid to even lunar orbit would dwarf the cost of dropping chunks of it onto the Utah salt flats or Death Valley. I’ll go even farther and say that the cost of prospecting the thousands of candidate asteroids to find the right one is even more daunting than prospecting the moon. A more logical process might be to mine the asteroid where it sits and only send the final product home, if it’s all going to be automated anyway.
If I wasn’t lazy and had more time, I’d calculate the amount of energy - in hydrogen-oxygen reaction presumably used as rocket fuel - to move 10 tons, say, of nickel from some earth approaching asteroid to low earth orbit; and how many tons of water that takes - and where we could get that sort of fuel (assuming solar power to separate the two gases). Instead I leave this as an exercise to the reader. I suspect that the cost of finding and providing that much reaction mass will make the material too expensive. What does a gallon of water in orbit cost?
(Which leads me to my next brainwave - solve the problem of propellant gas storage by storing it as frozen water, and electrolyze why you need with giant solar power panels as close to using it as is feasible. Less likely to have it all leak away, and no need for extremely large pressure vessels or thermos bottles.)
I’m reminded of Heinlein’s The Moon Is A Harsh Mistress. Which is also the name of a very nice song Jimmy Webb wrote.
Sigh.
DO you really, REALLY think that a parachute will help prevent part of the metal from burning up?
Right, the parachute can only be deployed once the big burning phase is over. Look at old Apollo films and such. Big hot ride until it slows down. Then pop the chute. Pop it earlier and the chute burns.
A chute is good for making sure the pod doesn’t go too deep into the ground on impact. It also allows better visual tracking if the radio goes dead. And the chute itself might be easier to spot after landing.
Yes, terminal velocity (air resistance = force of gravity) is usually unacceptably high for most dense objects like people and spacecraft, even at sea level atmospheric pressure. A parachute just raises the air resistance to a much higher level. Even so, the Soyuz, which landed on ground rather than water, still uses retro-rockets at the last minute to reduce the impact shock. One rule of thumb I recall from decades ago was that a typical parachute was usually the equivalent of a ten-foot drop; something easily survivable but risky if you did not prepare for impact.
Ditto. But let’s not ignore MISTRESS’ fantasy factor. Unless launching to Luna is REAL cheap, sending political prisoners there won’t happen. An Antarctic penal colony to farm with available H2O would be much more cost-effective. Or just shoot the troublemakers. But spending lots of resources to exile and guard malcontents who grow a few tonnes of grain to catapult Earthward? Right. :smack:
IIRC Niven’s Belters didn’t ship asteroids to Terra. Don’t expect future IRL humans to do so, either. What will be worth soft-landing from orbit to the bottom of Terra’s gravity well? Not heavy stuff (except maybe captured quantum black holes). People and other lifeforms. Drugs and materials grown in zero- or micro-gravity. What else?
Part of the point of The Moon is a Harsh Mistress was that the system was horribly inefficient. Something doesn’t need to be efficient or a good idea for people to do it. You just need a few important people who think it’s a good idea.
Power, assuming solar power satellites ever become economical. Information, in the form of a persistent surveillance net. (Assuming a mirror factory in space, with sufficient material and energy inputs, what size mirrors can be made?) Turn them the other way, and what new discoveries in astronomy might we find? Or increasing the potential warning time for a significant Earth-impacting body. As well as having, already in orbit, means for adjusting its orbit to miss us.
One thing the Moon provides is isolation for things that might go ‘BANG!’ E.g., automated antimatter factories. Or experiments with anything we’d just as soon not allow anywhere near Earth’s biosphere.
Surprisingly, this statement is rather significantly wrong.
Today, we are nowhere close to be able to remotely afford to exploit the Moon for anything. Even if you take SpaceX’s best projections as true, payload to the lunar surface will still be hundreds of dollars per kilogram. (say $100 a kilogram for orbiting payload for a SpaceX heavy lift rocket launch, then a 6:1 fuel : payload ratio for a lunar landing, also a translunar injection burn). Almost certainly at least $1000 a kg.
You aren’t mining profitably with that if the equipment costs too much to haul it over.
So you need factories on the Moon, a really small and light factory that can “bootstrap”, where it manufacturers all the rest of the industrial equipment needed.
It’s gonna need to be pretty automated, astronauts don’t get much done in balloon suits in a radiation field. Plus, why send astronauts, just run it remotely.
If the factory on the Moon is automated and can make more of itself…
Basically, I predict a whole lotta nothing - maybe decades worth, maybe centuries, then a tiny dot of light lands on the Moon. Then, in almost real time, you see an albedo change of a patch of the Lunar surface expanding to cover it all.