If your only goal is to separate our food production from nature then terrestrial hydroponics seem a far cheaper and easier solution. I’m not sure that’s much of a win though.
I’m back after doing rough figuring for the energy release landing a freighter-sized barge, and… the comment I was going to reply to is gone? sigh
Okay, this is scaled up from the PE and KE needed for a Soyuz to ISS orbit. (I’m not going to redo grade 11 physics this afternoon.)
9,000 kg to ISS height = 3.32 x 1010 Joules.
Add 5x that for the orbital KE = 1.992 x 1011 Joules.
Scale it up to a 90,000 tonne freighter = 1.992 x 1015 Joules.
That’s about half the energy released by a 1 megatonne H-bomb. Okay, not too bad for pure heat. Still, I wouldn’t want to be under the huge reentry footprint of that daily barge. If the long flash don’t get you, the shockwave will ruin your day.
I wonder how that’ll be for plants, animals, and air travel?
Note that’s from a 400 km LEO. Coming direct from the Moon would bump up the energy a lot.
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Who cares about them! Space mining!!! /s
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Here’s how asteroid mining will transform the world
Oh so needy mining billionaire convinces [$$$] authorities and related regulators that his asteroid would better serve “the public interest” by having its orbit altered, getting it closer to Earth for cheaper mining. Later, said asteroid accidentally deorbits and crashes into the world — thus transforming it.
OH yeah, THAT could happen!
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Current events have proven that anything really is possible now.
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It is 2020, the worst year in history (I am calling it).
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It feels that way. Being deep so far into Mary Trump’s real tales of horror, here’s another excerpt from her book: If he is afforded a second term, it would be the end of American Democracy.
That from a psychologist – an associate professor who “taught graduate courses in trauma, psychopathology, and developmental psychology” – who knows the Trump family history as well as (if not better than) anyone else.
Oh, well. I’ll get off that. Better to consider world ending asteroids.
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the way I interpret the video is that they are suggesting using the moon to capture the incoming asteroid via some exchange of the moon’s orbital energy with the asteroid, thereby establishing the asteroid in Earth orbit. The “refineries” they envision attach to the asteroid like a virus to a cell; each refinery is dedicated to the one asteroid. Must be better to send one small refinery to a remote asteroid than send the whole asteroid to the refinery, when you are only expecting to extract a small fraction of the asteroid’s mass. The capture of the asteroid will only require stealing energy from the Moon’s orbit ( hey, enough of these, maybe we could circularize the Moon’s orbit 
) but sending it on it’s way from the asteroid belt will require capital energy that would dwarf the requirement to send the much smaller refinery to the asteroid belt. Also, I imagine the refining methods they envision are somewhat similar to epitaxial deposition processes done on a large scale, so being in strong gravitational fields might be a disadvantage. If anything, I think this video is lacking in vision and the Earth centric framing of asteroid mining is kind of alarmist (woo, asteroids coming at us from all angles) .
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While so many have been jumping on the asteroid hype train, one of the few start-up companies founded to actually pursue asteroid mining went bankrupt last year for lack of interest or investment from any those very same people who keep telling us how important this all is.
Sometimes people’s intentions are as much communicated by what they don’t do as by what they do. Like when someone keeps telling you about their plans for an overseas trip, and yet they never seem to get around to packing their bags. Or they tell you about the dream house they’re building, but never seem to get around to buying any tools or lumber.
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For now, we need to learn to stop producing more crap so some jerk in the Hamptons can get themselves another super yacht then maybe we can stop mining as much.
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I wasn’t really asking how it happened, I was wondering how it affected the economy. From what I’ve learned informally, the market simply accepted the new status quo and rolled with it. I’m sure there were a few aluminum millionaires who crashed, I figure most people who purchased aluminum for their own products quickly moved into other (larger) markets and made out like bandits.
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Apologies! Totally misread your comment.
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