epistemic status: speculation backed by ~no reading
Asteroid mining is under-valued as an application of better rocket technology: clear economic advantage (rare metals that on earth have mostly accumulated in the core), no gravity wells to overcome, high potential for automation.
Compare to space colonisation: No economic advantage (instead probably a giant money-sink & a titanic public good), health problems galore (or planetary gravity wells humans want to get into & out of).
A potential problem with asteroid mining would be getting the mined material back onto earth: if we mine as much rare earths on asteroids as on earth right now per year (~250 kilotons), and dropped these onto earth, would the resulting energy be large enough to cause significant climate change? Or is it okay if we just drop the stuff into shallow oceans somewhere?
[ have read some essays on the topic over the last ~40 years, but nothing rigorous or recent. ]
We’re quite a ways from being able to get there cheaply enough, with cheap and robust enough autonomous machinery (it’s probably not going to be recovered or sent to the next location after it’s identified an attachment point and mined what it can reach) to make it work.
And that’s separate from the problem of getting it safely to earth—I can imagine a two-part process for that—unmanned return rockets which get it to earth orbit, and then retrieval devices to get it to orbital processing plants (which are also decades away). Use in orbit is obvious. Refinement to a purity that makes it feasible to get to earth is also likely.
Similar epistemic status, but I believe it’s almost as difficult to lower large masses safely into a gravity well as to lift them out. All that potential energy has to go somewhere.
ETA: 100 tons hitting the Earth’s surface at Earth escape speed releases the energy of 1.2 kilotons of TNT, causing an earthquake of magnitude 5 on the Richter scale,
The energy input is absolutely trivial compared to sunlight; climate change is driven by changing radiation balances not energy inputs (on anything like this scale).
You’d want to do a lot of aerobraking just to keep your metals easy-to-collect instead of dispersing them across the landscape. Expect regulatory issues anyway, since you’ve just built a dispenser of expensive rods from god.
epistemic status: speculation backed by ~no reading
Asteroid mining is under-valued as an application of better rocket technology: clear economic advantage (rare metals that on earth have mostly accumulated in the core), no gravity wells to overcome, high potential for automation.
Compare to space colonisation: No economic advantage (instead probably a giant money-sink & a titanic public good), health problems galore (or planetary gravity wells humans want to get into & out of).
A potential problem with asteroid mining would be getting the mined material back onto earth: if we mine as much rare earths on asteroids as on earth right now per year (~250 kilotons), and dropped these onto earth, would the resulting energy be large enough to cause significant climate change? Or is it okay if we just drop the stuff into shallow oceans somewhere?
[ have read some essays on the topic over the last ~40 years, but nothing rigorous or recent. ]
We’re quite a ways from being able to get there cheaply enough, with cheap and robust enough autonomous machinery (it’s probably not going to be recovered or sent to the next location after it’s identified an attachment point and mined what it can reach) to make it work.
And that’s separate from the problem of getting it safely to earth—I can imagine a two-part process for that—unmanned return rockets which get it to earth orbit, and then retrieval devices to get it to orbital processing plants (which are also decades away). Use in orbit is obvious. Refinement to a purity that makes it feasible to get to earth is also likely.
Similar epistemic status, but I believe it’s almost as difficult to lower large masses safely into a gravity well as to lift them out. All that potential energy has to go somewhere.
ETA: 100 tons hitting the Earth’s surface at Earth escape speed releases the energy of 1.2 kilotons of TNT, causing an earthquake of magnitude 5 on the Richter scale,
The energy input is absolutely trivial compared to sunlight; climate change is driven by changing radiation balances not energy inputs (on anything like this scale).
You’d want to do a lot of aerobraking just to keep your metals easy-to-collect instead of dispersing them across the landscape. Expect regulatory issues anyway, since you’ve just built a dispenser of expensive rods from god.