5 ms·

There's a simple point about space elevators that most people ignore. We would only build a space elevator if it made economic sense. Given the reality of con

by dekhn 2y ago

There's a simple point about space elevators that most people ignore. We would only build a space elevator if it made economic sense. Given the reality of construction costs, even if we had the materials, it would like cost many trillions of dollars (at least) so whatever we used it for would have to produce much more value than that. Even more importantly, if we had access to the materials necessary to build space elevators, there are other, much more pressing terrestrial needs that would use up all those materials long before somebody tried to build an elevator. No matter how much fun it is to contemplate their existence, nobody has come up with a justification for the necessary investment required to build and operate one.

darby_nine 2y ago
> Given the reality of construction costs, even if we had the materials, it would like cost many trillions of dollars (at least) so whatever we used it for would have to produce much more value than that. This doesn't seem that difficult given the potential value of mining. I suspect terrestrial politics would dominate this conversation—access to said elevator is far more interesting than any collective concern, and humans as they stand are not capable of resolving collective concerns on any level.
- dekhn 2y ago
  Trillions+ in mining value? What exactly are you proposing mining (platinum seems the most likely, IIRC my D&D)? remember that new sources affect the supply, which changes prices significantly, so it would have to be basically unobtanium to be worth it. And remember, since you developed all that tech just to make the space elevator... most of the mining you did is probably obsolete.
  - ben_w 2y ago
    Even aluminium gets you to a trillion dollars in 6 years. https://en.wikipedia.org/wiki/List_of_countries_by_aluminium_production https://en.wikipedia.org/wiki/List_of_countries_by_aluminium... * Calculation: http://www.wolframalpha.com/input/?i=1%20trillion%20USD%20%2F%20%28aluminium%20price%20%2A%2064%20million%20tons%20per%20year%29 http://www.wolframalpha.com/input/?i=1%20trillion%20USD%20%2... * Old data, China has rapid growth in this sector and is now about 42 megatons/y, but that just changes the result from rounding down to 6 years to rounding up to 6 years: https://www.reuters.com/markets/commodities/china-2023-aluminium-output-hits-record-high-growth-rate-slows-2024-01-17/ https://www.reuters.com/markets/commodities/china-2023-alumi...
    - dekhn 2y ago
      Aluminum is widely available in the earth and if you approached earth with a new delivery at scale, prices would fall through the floor.
      - darby_nine 2y ago
        So would the cost of building space elevators. I'm betting there wouldn't be a single part of society unaffected by an explosion of raw materials at much lower cost. It's just an insanely high investment cost to kick off the industrialization of space. Besides, mining on earth has many externalities that aren't reflected in the commodity price. Some of the most brutal and inhumane conditions on earth right now are tied directly to market demand for rare or difficult to aggregate minerals. The sooner we can shut that down the sooner we can claim social progress without ten asterisks trailing it.
      - ben_w 2y ago
        That aluminium is widely available on earth was necessary to my point that it is trivial to find existing examples in the trillion-dollar scale. Aluminium prices would only fall if you were selling the whole thing in one go for instant delivery — unusually for most supplies this form of delivery would be technically possible, but RFGs are normally considered "weapons" rather than "shipping". Look at how much supply has increased this century vs. price: production has seen near-continuous growth while the price has been spiky rather than a consistent downward trend, this is because aluminium is *really useful*. Given that orbital dynamics makes it more like a months-to-years process just to get to the asteroid in the first place, who knows how long to capture it and stabilise for mining etc., and that mining itself would not be an instant process even if we happen to get a convenient pile of purely metallic (non-oxidised) rubble, it won't be all on the market for instant delivery. I get similar values for copper: https://www.wolframalpha.com/input?i=1+trillion+USD+%2F+%28%2822+million+tonnes+%2F+year%29+*+price+of+copper%29 https://www.wolframalpha.com/input?i=1+trillion+USD+%2F+%28%... Zinc is ~ 30 years of global production at current prices, which would be pushing it for a corporate investment but not totally implausible: https://www.wolframalpha.com/input?i=1+trillion+USD+%2F+%28%2814.13+million+tons+%2F+year%29+*+price+of+zinc%29 https://www.wolframalpha.com/input?i=1+trillion+USD+%2F+%28%... Just under 4 years for iron ore: https://www.wolframalpha.com/input?i=1+trillion+USD+%2F+%28%282.5e9+tons+%2F+year%29+*+%28%24104.00%2Fton%29 https://www.wolframalpha.com/input?i=1+trillion+USD+%2F+%28%... Just over 4 years for gold: https://www.wolframalpha.com/input?i=1+trillion+USD+%2F+%28%283%2C000+metric+tons+%2F+year%29+*+%28price+gold%29 https://www.wolframalpha.com/input?i=1+trillion+USD+%2F+%28%... I think aiming for a trillion USD of platinum would indeed crash the market, as the same formula gives me 180 years for that: https://www.wolframalpha.com/input?i=1+trillion+USD+%2F+%28%28180+tons+%2F+year%29+*+%28price+platinum%29 https://www.wolframalpha.com/input?i=1+trillion+USD+%2F+%28%...
efitz 2y ago
I am willing to bet that Elon Musk and SpaceX are doing the calculations very carefully and will build a space elevator if technology advances make it more cost effective than reusable rockets to get to Mars.
richk449 2y ago
Many technologies are developed long before they are viable because they have military value. Access to space is currently a major national security issue, so a space elevator could be a manhattan project. Some technologies are developed by the free market before they are economically viable too. LEO constellations for instance (both the original - iridium, and starlink).
- schiffern 2y ago
  >developed by the free market >iridium For some reason I was skeptical of this (suspiciously tidy) myth-making, and the more I look into it the more I'm convinced I was right to be skeptical. Turns out the relevant engineers -- Ken Peterson and Ray Leopold -- both worked on military and government communications systems immediately prior to being hired at Motorola and starting the Iridium project. Peterson's bio is rather vague on timelines[0], but available information on Leopold indicates he joined Motorola in 1987[1] (directly from the Air Force Electronic Systems Division,[2] which develops communication systems), which is the same year he and Peterson started work on Iridium.[3] This has all the hallmarks of one of those nice neat (and of course plausibly deniable) tech transfers from military/taxpayer dollars, complete with the cute official origin story featuring a C-suite executive's wife. [0] https://www.tributearchive.com/obituaries/25954530/ken-peterson https://www.tributearchive.com/obituaries/25954530/ken-peter... [1] https://ocw.mit.edu/courses/16-886-air-transportation-systems-architecting-spring-2004/473718b4c5f8d9b64cba2f56413c12a0_h16rayleopoldbio.pdf https://ocw.mit.edu/courses/16-886-air-transportation-system... [2] https://en.wikipedia.org/wiki/Electronic_Systems_Center https://en.wikipedia.org/wiki/Electronic_Systems_Center [3] https://www.laits.utexas.edu/~anorman/long.extra/Student.F98/Iridium/Frames/FirstRight.html https://www.laits.utexas.edu/~anorman/long.extra/Student.F98...
  - richk449 2y ago
    Pretty much everything that has to do with space was first developed by governments for military purposes. Rockets, satellites, communications, imaging, etc. I think your point supports the general thesis that many technologies are developed before they are economically viable.
Vecr 2y ago
How's laser launch research come since the 1970s? It's probably limited to launching metal hardware, but when the cost of a space elevator is compared to making a bunch really big lasers and putting them radially around some mirrors, it's something to think about. Is it an overheating problem? The mirrors and optics would just get fried?

by dekhn 2y ago

darby_nine 2y ago

> Given the reality of construction costs, even if we had the materials, it would like cost many trillions of dollars (at least) so whatever we used it for would have to produce much more value than that. This doesn't seem that difficult given the potential value of mining. I suspect terrestrial politics would dominate this conversation—access to said elevator is far more interesting than any collective concern, and humans as they stand are not capable of resolving collective concerns on any level.

dekhn 2y ago
Trillions+ in mining value? What exactly are you proposing mining (platinum seems the most likely, IIRC my D&D)? remember that new sources affect the supply, which changes prices significantly, so it would have to be basically unobtanium to be worth it. And remember, since you developed all that tech just to make the space elevator... most of the mining you did is probably obsolete.
- ben_w 2y ago
  Even aluminium gets you to a trillion dollars in 6 years. https://en.wikipedia.org/wiki/List_of_countries_by_aluminium_production https://en.wikipedia.org/wiki/List_of_countries_by_aluminium... * Calculation: http://www.wolframalpha.com/input/?i=1%20trillion%20USD%20%2F%20%28aluminium%20price%20%2A%2064%20million%20tons%20per%20year%29 http://www.wolframalpha.com/input/?i=1%20trillion%20USD%20%2... * Old data, China has rapid growth in this sector and is now about 42 megatons/y, but that just changes the result from rounding down to 6 years to rounding up to 6 years: https://www.reuters.com/markets/commodities/china-2023-aluminium-output-hits-record-high-growth-rate-slows-2024-01-17/ https://www.reuters.com/markets/commodities/china-2023-alumi...
  - dekhn 2y ago
    Aluminum is widely available in the earth and if you approached earth with a new delivery at scale, prices would fall through the floor.
    - darby_nine 2y ago
      So would the cost of building space elevators. I'm betting there wouldn't be a single part of society unaffected by an explosion of raw materials at much lower cost. It's just an insanely high investment cost to kick off the industrialization of space. Besides, mining on earth has many externalities that aren't reflected in the commodity price. Some of the most brutal and inhumane conditions on earth right now are tied directly to market demand for rare or difficult to aggregate minerals. The sooner we can shut that down the sooner we can claim social progress without ten asterisks trailing it.
    - ben_w 2y ago
      That aluminium is widely available on earth was necessary to my point that it is trivial to find existing examples in the trillion-dollar scale. Aluminium prices would only fall if you were selling the whole thing in one go for instant delivery — unusually for most supplies this form of delivery would be technically possible, but RFGs are normally considered "weapons" rather than "shipping". Look at how much supply has increased this century vs. price: production has seen near-continuous growth while the price has been spiky rather than a consistent downward trend, this is because aluminium is *really useful*. Given that orbital dynamics makes it more like a months-to-years process just to get to the asteroid in the first place, who knows how long to capture it and stabilise for mining etc., and that mining itself would not be an instant process even if we happen to get a convenient pile of purely metallic (non-oxidised) rubble, it won't be all on the market for instant delivery. I get similar values for copper: https://www.wolframalpha.com/input?i=1+trillion+USD+%2F+%28%2822+million+tonnes+%2F+year%29+*+price+of+copper%29 https://www.wolframalpha.com/input?i=1+trillion+USD+%2F+%28%... Zinc is ~ 30 years of global production at current prices, which would be pushing it for a corporate investment but not totally implausible: https://www.wolframalpha.com/input?i=1+trillion+USD+%2F+%28%2814.13+million+tons+%2F+year%29+*+price+of+zinc%29 https://www.wolframalpha.com/input?i=1+trillion+USD+%2F+%28%... Just under 4 years for iron ore: https://www.wolframalpha.com/input?i=1+trillion+USD+%2F+%28%282.5e9+tons+%2F+year%29+*+%28%24104.00%2Fton%29 https://www.wolframalpha.com/input?i=1+trillion+USD+%2F+%28%... Just over 4 years for gold: https://www.wolframalpha.com/input?i=1+trillion+USD+%2F+%28%283%2C000+metric+tons+%2F+year%29+*+%28price+gold%29 https://www.wolframalpha.com/input?i=1+trillion+USD+%2F+%28%... I think aiming for a trillion USD of platinum would indeed crash the market, as the same formula gives me 180 years for that: https://www.wolframalpha.com/input?i=1+trillion+USD+%2F+%28%28180+tons+%2F+year%29+*+%28price+platinum%29 https://www.wolframalpha.com/input?i=1+trillion+USD+%2F+%28%...

efitz 2y ago

I am willing to bet that Elon Musk and SpaceX are doing the calculations very carefully and will build a space elevator if technology advances make it more cost effective than reusable rockets to get to Mars.

richk449 2y ago

Many technologies are developed long before they are viable because they have military value. Access to space is currently a major national security issue, so a space elevator could be a manhattan project. Some technologies are developed by the free market before they are economically viable too. LEO constellations for instance (both the original - iridium, and starlink).

schiffern 2y ago
>developed by the free market >iridium For some reason I was skeptical of this (suspiciously tidy) myth-making, and the more I look into it the more I'm convinced I was right to be skeptical. Turns out the relevant engineers -- Ken Peterson and Ray Leopold -- both worked on military and government communications systems immediately prior to being hired at Motorola and starting the Iridium project. Peterson's bio is rather vague on timelines[0], but available information on Leopold indicates he joined Motorola in 1987[1] (directly from the Air Force Electronic Systems Division,[2] which develops communication systems), which is the same year he and Peterson started work on Iridium.[3] This has all the hallmarks of one of those nice neat (and of course plausibly deniable) tech transfers from military/taxpayer dollars, complete with the cute official origin story featuring a C-suite executive's wife. [0] https://www.tributearchive.com/obituaries/25954530/ken-peterson https://www.tributearchive.com/obituaries/25954530/ken-peter... [1] https://ocw.mit.edu/courses/16-886-air-transportation-systems-architecting-spring-2004/473718b4c5f8d9b64cba2f56413c12a0_h16rayleopoldbio.pdf https://ocw.mit.edu/courses/16-886-air-transportation-system... [2] https://en.wikipedia.org/wiki/Electronic_Systems_Center https://en.wikipedia.org/wiki/Electronic_Systems_Center [3] https://www.laits.utexas.edu/~anorman/long.extra/Student.F98/Iridium/Frames/FirstRight.html https://www.laits.utexas.edu/~anorman/long.extra/Student.F98...
- richk449 2y ago
  Pretty much everything that has to do with space was first developed by governments for military purposes. Rockets, satellites, communications, imaging, etc. I think your point supports the general thesis that many technologies are developed before they are economically viable.

Vecr 2y ago

How's laser launch research come since the 1970s? It's probably limited to launching metal hardware, but when the cost of a space elevator is compared to making a bunch really big lasers and putting them radially around some mirrors, it's something to think about. Is it an overheating problem? The mirrors and optics would just get fried?