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Mine the moon? That's a pretty stupid idea. Much better to aim for an asteroid - no property rights and no gravity well to escape afterwards. Net value of the r

Mine the moon? That's a pretty stupid idea. Much better to aim for an asteroid - no property rights and no gravity well to escape afterwards. Net value of the rare earths in a 1 km asteroid was ~1 trillion dollars, from memory. There aren't any trojan asteroids in the earth-moon system according to http://map.gsfc.nasa.gov/mission/observatory_l2.html http://map.gsfc.nasa.gov/mission/observatory_l2.html, but there are quite a few close approachers which could potentially be redirected closer to Earth. btw, this is not a new idea, so there's no excuse for not knowing about this, especially if you're in the field: http://www.nss.org/settlement/L5news/1982-harvesting.htm http://www.nss.org/settlement/L5news/1982-harvesting.htm

HelloBeautiful 16y ago
Those close approaches are moving very fast. Plus who would wont some limited liability startup to redirect asteroids closer to Earth, probably using big thermonukes?
- anthonyb 16y ago
  Objects in orbit are also moving pretty fast. Slowing it down a bit so that it's captured by Earth's orbit wouldn't take that much energy. Also, mass drivers would be the preferred option, no nukes necessary. A 200 metre asteroid might make a pretty big hole, but then so would profitable quantities of ore coming back, or a rocket capable of getting to the moon in the first place. Nobody seems to be too worried about SpaceX accidentally crashing their moon-capable rockets into a city.
  - JshWright 16y ago
    Seriously? You're comparing a rocket with a self-destruct button to an uncontrolled projectile with several hundred times more mass?
    - anthonyb 16y ago
      Several hundred? I think you're at least a couple of orders of magnitude out there... The point behind the rocket analogy was that rockets are inherently dangerous, uncontrolled projectiles. They explode, spin out of control, travel at hundreds or thousands of km/hr - but that's apparently ok. And it is, because there are safeguards in place. a) how are you getting the ore back to earth? Your choice is to either burn it back in on a rocket or splash down your hundred or thousand tons of platinum somewhere. Rockets are hideously expensive, which leaves you with... an uncontrolled projectile. b) mass drivers have a small amount of thrust, over a long period of time. It might take a couple of years to get it captured by earth - think slow orbit corrections over time rather than an uncontrolled asteroid missile. Once you get to that point, you'll have several more years to circularise the orbit. Hardly an uncontrolled projectile - Its path is easy to predict, and is incredibly unlikely to hit the earth. You'd need to burn a lot of energy to do so once it's in a stable orbit.
      - JshWright 16y ago
        Yep... you're right... s/several hundred/thousands/ My main point is that rockets have a big red button, and an 8,000,000,000kg rock does not.
        anthonyb 16y ago
        Well, yes - but asteroids have plenty of time to correct, whereas a rocket doesn't. The safety measures are likely to be completely different.

HelloBeautiful 16y ago

Those close approaches are moving very fast. Plus who would wont some limited liability startup to redirect asteroids closer to Earth, probably using big thermonukes?

anthonyb 16y ago
Objects in orbit are also moving pretty fast. Slowing it down a bit so that it's captured by Earth's orbit wouldn't take that much energy. Also, mass drivers would be the preferred option, no nukes necessary. A 200 metre asteroid might make a pretty big hole, but then so would profitable quantities of ore coming back, or a rocket capable of getting to the moon in the first place. Nobody seems to be too worried about SpaceX accidentally crashing their moon-capable rockets into a city.
- JshWright 16y ago
  Seriously? You're comparing a rocket with a self-destruct button to an uncontrolled projectile with several hundred times more mass?
  - anthonyb 16y ago
    Several hundred? I think you're at least a couple of orders of magnitude out there... The point behind the rocket analogy was that rockets are inherently dangerous, uncontrolled projectiles. They explode, spin out of control, travel at hundreds or thousands of km/hr - but that's apparently ok. And it is, because there are safeguards in place. a) how are you getting the ore back to earth? Your choice is to either burn it back in on a rocket or splash down your hundred or thousand tons of platinum somewhere. Rockets are hideously expensive, which leaves you with... an uncontrolled projectile. b) mass drivers have a small amount of thrust, over a long period of time. It might take a couple of years to get it captured by earth - think slow orbit corrections over time rather than an uncontrolled asteroid missile. Once you get to that point, you'll have several more years to circularise the orbit. Hardly an uncontrolled projectile - Its path is easy to predict, and is incredibly unlikely to hit the earth. You'd need to burn a lot of energy to do so once it's in a stable orbit.
    - JshWright 16y ago
      Yep... you're right... s/several hundred/thousands/ My main point is that rockets have a big red button, and an 8,000,000,000kg rock does not.
      - anthonyb 16y ago
        Well, yes - but asteroids have plenty of time to correct, whereas a rocket doesn't. The safety measures are likely to be completely different.