It’s a staple of science fiction that the moon gets mined to provide resources for battle fleets / onward expansion / whatever. But, supposing we get mega-scale manufacturing sorted out, how would a reduction in the mass of the moon affect the Earth? As I understand it, the moon is rather vital in keeping the Earth stable, as well as causing tides and the like.
And if we can’t mine the moon, could we safely mine other planets without affecting the Earth? Like Mars
The moon is a really, really big place, even if it is smaller than the Earth. It would take a really, really long time to mine enough it to make a difference. You might as well express concern that we’re mining the Earth and firing stuff made from bits of it into space.
What exactly would we mine on the moon? It seems like an expensive way to get minerals that probably we can get on earth a lot more cheaply.
Well, expense depends on the objective. For minerals to be used on earth, yes, I’m not sure that there are many available on the moon that would be worth the effort.
Lunar mining would, OTOH, be a keystone in my opinion to any kind of continuing space endeavour, because setting up a lunar mining base and using construction materials from there would be cheaper than actually blasting the same mass up out of the Earth’s gravity well on rockets.
I’m certainly not an authority on the subject, but i randomly saw a documentary about this a while ago. Helium-3
I understand why we wouldn’t want go to back to the moon.
Louis Armstrong went up there in the 60’s… walked around a bit, came home.
He hasn’t been back since; that says alot don’t it?
How much of the moon is usefull? It doesn’t have very much metal I know.
That’s why I said mega-scale mining. Imagine we’re building a Death Star or three. Could we safely take 10% of the moon? 5%?
Satchmo went to the Moon?
If you get to that level of space exploration/exploitation, its pretty much easier in EVERY way to mine comets and asteriods.
Comets for the stuff like water and gasses.
Asteroids for the heavier stuff.
And there are literally thousands of comets and tens of thousands of asteroids. Even the tiniest of em represents a metric shit load of stuff.
Dropping back into a deep gravity well like Mars or even the Moon just doesn’t make sense for materials, unless you are there to EXPLORE THAT place.
Its kind of like landing an already flying 747 so you can use the microwave at the local Seven Eleven.
Ask Karl Pilkington. It will make less sense, and involve a monkey (which might probably be an ape,) but will leave you none-the-less both over- & under-whelmed.
As the moon and the Earth were once both part of a larger planetary body I would imagine that they share the same minerals etc. so on that score its probable that there is something worth mining up there .
I get your point about having to escape the Earths gravity well etc. making lunar mining more expensive but once all the equipment and infrastructure is in place then it would be a much more easier and cheaper matter to send mined resources back down to Earth.
Also we must bear in mind that we are depleting our planets accessible resources daily and that there will come a point when it will become a case of getting what we need from off world or not at all.
Not true, yeah moon and earth share the same stuff…BUTTTT most of the good stuff has settled to the core in both the earth and the moon. If it weren’t for volcanic activity on earth, most of the good stuff would be even HARDER to get to than it already is. The moon has had little volcanic activity in comparision. At least thats my understanding.
Small planetary bodies don’t have that problem. They are much more likely to be somewhat uniformly distributed elements wise.
Also, because of the way the moon formed…its been baked bone ass dry. Actually it was sorta twice baked compared to most other bodies in the solar system. Most of the more volatile elements have been driven off or at least greatly reduced. Not so on smaller bodies.
The ONLY real advantage the moon has over comets or asteroids it that its CLOSE in distance/time. Note that close does NOT mean it takes less energy to get to land on and take off again. Its mostly just close.
Once you get to the point that you can even support a few dozen/hundred human “miners” in space for long periods of time (months/years), its better to just bypass the moon altogether.
Its NOT cheaper or easier unless you can MAKE rockets on the moon very cheapley and easy to get out of that gravity well. And even then almost by definition coming back from an asteroid would be cheaper and easier still.
time/distance is about the only thing the moon has going for it
Nonsense.
Biological resources are generally renewed/renewable and are not available from offworld anyway (or at least we hope so).
We are very definately consuming oil / coal, IOW ancient bio resources. Not much eveidence that there’s any of that to be found out in space. Plenty of frozen methane though.
But we’re not consuming iron or copper or gold or water … IOW the things we might be able to get off-planet, particularly from the Moon. Sure, we’re digging various ores out of the ground, but all of it ends up back in the earth in an even more concentrated form called a car graveyard, landifll, sunken ship, or similar.
Many folks look at mining & refniement into raw materials as somehow pretty simple or pretty natural. Not really. A lot of technology on a massive scale is required to turn a pile of red dirt into a coil of sheet steel.
Some day we’ll be mining the landfills & junkyards in addition to the natural ore deposits. The industrial processes will be different for sure, but they’ll be working from a much richer ore bed and there’s no reason to assume the costs will be prohibitive.
As (if?) we get smarter about long term gain vs short term cost, we can expect to see more post-use recycling as a way to be even more efficient=profitable versus dumping followed by extraction later. e.g. per Aluminium recycling - Wikipedia about 30% of the raw aluminum produced in the US today is from recycled material, not from ore.
Bottom line: We’re moving iron & other minerals around, not consuming them.
But we got a beautiful song out of it:
I think that was worthwhile.
The mass of the moon is approximately 7.4 x 10 [sup]22[/sup] kg.
That’s 74,000,000,000,000,000,000,000 kg.
The world iron production is about 1,000,000,000,000 kg.
It would take longer than the age of the earth to take even 10% of the moon away at that rate.
I don’t think it’s an issue.
Of course, that’s why we named an airport after him!
Old Gahan Wilson cartoon:
Little boy and mother looking up at the sky, which contains a moon shaped like an apple core. Mother is saying:
“It all started back in 1969 with a couple rocks”.
No, mining of asteroids and Near Earth Objects would be key to developing a self-sustaining human presence in space. Although the Moon’s gravity is only 1/6th that of Earth, it still is a significant well to drag things out of, and then you have to boost them into whatever orbit (or into an Earth escape trajectory if you are going into an interplanetary orbit) to get where you want to go. On the other hand, small objects have essentially no gravity field and you can select one judiciously close in energy and trajectory to your final locus that it costs you little to get raw materials there. In the in-system (inside the orbit of Jupiter) you can also use light pressure from the Sun to boost into different orbits if you aren’t in a particular hurry.
Although D-[sup]3[/sup]He fusion would be desirable from the standpoint of low neutron emissions (which are destructive to structural materials and can activate normally stable elements), the fact is that we can’t even achieve breakeven output with D-T fusion. Given that D-[sup]3[/sup]He has a Lawson criteria of 16 (the product of required temperature, plasma density, and confinement time to achieve fusion) and a power factor of 26.4 (the ratio of fusion power output to power losses within the plasma) compared to D-T fusion, any presumption based upon the utility of [sup]3[/sup]He is speculative at best. In any case, the best way to collect [sup]3[/sup]He is just probably to place large traps in space near the Sun (which spits it out on a steady basis) or mine it from comets, not grind up lunar regolith for it.
Stranger