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Raw metal powder for 3D printing laser sintering. Or plastic pellets. Water. Fuel. Clothes. Maybe this is what can kick start the 3D printing in space revolut

Raw metal powder for 3D printing laser sintering. Or plastic pellets. Water. Fuel. Clothes. Maybe this is what can kick start the 3D printing in space revolution. Maybe it can also launch radioactive waste into space? One bucket at a time. Then a space towtruck can be launched to hurl it into the sun. But it’ll likely just part a naive investor from their money.

Cthulhu_ 6y ago
Not sure how serious you are with the radioactive waste thing but I'll do the HN thing and bite (nerdsnipe!), because that's not going to work. You can't launch things into the sun, you need to decelerate objects. The earth travels at 30 km / s (70K MPH) around the sun, so you need to decelerate about that much the other way. And orbiting radioactive waste is just asking for trouble. The total amount of radioactive waste on the earth is about the size of a swimming pool (or was that the total amount of gold? I forgot, either way in terms of quantity it's not that much), burying it deep and forgetting about it for the next 100.000 years is the way to go I think.
- piker 6y ago
  > The total amount of radioactive waste on the earth is about the size of a swimming pool (or was that the total amount of gold? I forgot, either way in terms of quantity it's not that much) This seems wrong in both places. There are probably enough gold rings manufactured per year to fill a swimming pool. In pictures: Fort Knox itself seems to have at least a swimming pool of gold [1] and Thailand a swimming pool of waste.[2] [1] https://external-preview.redd.it/rgD0FO1pELgkuXZzWC2NQk0vJZUUjxMl6o9MBX7WwDM.jpg?auto=webp&s=80a721910b3891129eeec2cca8d1815f58f33abf https://external-preview.redd.it/rgD0FO1pELgkuXZzWC2NQk0vJZU... [2] https://upload.wikimedia.org/wikipedia/commons/9/93/TINT_Radioactive_wastes%27_barrel.jpg https://upload.wikimedia.org/wikipedia/commons/9/93/TINT_Rad...
  - nitrogen 6y ago
    Those piles of bars are shallow, and those barrels are probably mostly non-spent-fuel by volume.
    - fanf2 6y ago
      In the 1930s they put about 13,000 tonnes of gold in Fort Knox. (It now has about 4,500 tonnes). Density of gold is about 20g/cm^3, or 20 tonnes per cubic metre. So Fort Knox held up to 650m^3 of gold. A normal swimming pool is about 25m x 12.5m x 2m which is 625m^3. https://en.wikipedia.org/wiki/United_States_Bullion_Depository https://en.wikipedia.org/wiki/United_States_Bullion_Deposito... This page indicates Sellafield has 2000m^3 of high level nuclear waste. https://ukinventory.nda.gov.uk/site/sellafield/ https://ukinventory.nda.gov.uk/site/sellafield/
      - beervirus 6y ago
        > Reported volume: This is the volume actually taken up by wastes that exist at the Inventory stock date. It is the volume taken up by wastes inside the tanks, vaults, silos and drums in which they are contained.
- redis_mlc 6y ago
  > you need to decelerate objects. Not if you aim it directly at the sun. > The total amount of radioactive waste on the earth is about the size of a swimming pool The HN nuclear apologists are so tiresome. No, every nuclear plant has more than that. Fukushima has acres, so they're dumping it in the ocean.
- Havoc 6y ago
  >The earth travels at 30 km / s (70K MPH) around the sun, so you need to decelerate about that much the other way. Surely you’d just need enough to end up in a decaying orbit? Then it’ll eventually reach the sun
  - jl2718 6y ago
    All you need to do is hit the Lagrange point.
  - hollerith 6y ago
    Low-earth orbits decay because of friction between the spacecraft and the Earth's upper atmosphere. What do you imagine would guarantee the decay of a solar orbit before a perturbation (by, e.g., the gravity of the Earth's moon or a comet) sends the orbiting object into a collision course with Earth?
- extraduder_ire 6y ago
  > burying it deep and forgetting about it for the next 100.000 years is the way to go I think. Is there a problem with burying it in a subducting plate boundary, so it is eventually pulled back into the earth's mantle? There's already fission going on down there.

Cthulhu_ 6y ago

Not sure how serious you are with the radioactive waste thing but I'll do the HN thing and bite (nerdsnipe!), because that's not going to work. You can't launch things into the sun, you need to decelerate objects. The earth travels at 30 km / s (70K MPH) around the sun, so you need to decelerate about that much the other way. And orbiting radioactive waste is just asking for trouble. The total amount of radioactive waste on the earth is about the size of a swimming pool (or was that the total amount of gold? I forgot, either way in terms of quantity it's not that much), burying it deep and forgetting about it for the next 100.000 years is the way to go I think.

piker 6y ago
> The total amount of radioactive waste on the earth is about the size of a swimming pool (or was that the total amount of gold? I forgot, either way in terms of quantity it's not that much) This seems wrong in both places. There are probably enough gold rings manufactured per year to fill a swimming pool. In pictures: Fort Knox itself seems to have at least a swimming pool of gold [1] and Thailand a swimming pool of waste.[2] [1] https://external-preview.redd.it/rgD0FO1pELgkuXZzWC2NQk0vJZUUjxMl6o9MBX7WwDM.jpg?auto=webp&s=80a721910b3891129eeec2cca8d1815f58f33abf https://external-preview.redd.it/rgD0FO1pELgkuXZzWC2NQk0vJZU... [2] https://upload.wikimedia.org/wikipedia/commons/9/93/TINT_Radioactive_wastes%27_barrel.jpg https://upload.wikimedia.org/wikipedia/commons/9/93/TINT_Rad...
- nitrogen 6y ago
  Those piles of bars are shallow, and those barrels are probably mostly non-spent-fuel by volume.
  - fanf2 6y ago
    In the 1930s they put about 13,000 tonnes of gold in Fort Knox. (It now has about 4,500 tonnes). Density of gold is about 20g/cm^3, or 20 tonnes per cubic metre. So Fort Knox held up to 650m^3 of gold. A normal swimming pool is about 25m x 12.5m x 2m which is 625m^3. https://en.wikipedia.org/wiki/United_States_Bullion_Depository https://en.wikipedia.org/wiki/United_States_Bullion_Deposito... This page indicates Sellafield has 2000m^3 of high level nuclear waste. https://ukinventory.nda.gov.uk/site/sellafield/ https://ukinventory.nda.gov.uk/site/sellafield/
    - beervirus 6y ago
      > Reported volume: This is the volume actually taken up by wastes that exist at the Inventory stock date. It is the volume taken up by wastes inside the tanks, vaults, silos and drums in which they are contained.
redis_mlc 6y ago
> you need to decelerate objects. Not if you aim it directly at the sun. > The total amount of radioactive waste on the earth is about the size of a swimming pool The HN nuclear apologists are so tiresome. No, every nuclear plant has more than that. Fukushima has acres, so they're dumping it in the ocean.
Havoc 6y ago
>The earth travels at 30 km / s (70K MPH) around the sun, so you need to decelerate about that much the other way. Surely you’d just need enough to end up in a decaying orbit? Then it’ll eventually reach the sun
- jl2718 6y ago
  All you need to do is hit the Lagrange point.
- hollerith 6y ago
  Low-earth orbits decay because of friction between the spacecraft and the Earth's upper atmosphere. What do you imagine would guarantee the decay of a solar orbit before a perturbation (by, e.g., the gravity of the Earth's moon or a comet) sends the orbiting object into a collision course with Earth?
extraduder_ire 6y ago
> burying it deep and forgetting about it for the next 100.000 years is the way to go I think. Is there a problem with burying it in a subducting plate boundary, so it is eventually pulled back into the earth's mantle? There's already fission going on down there.