Small Asteroid Mining (Geology, Economic and Ecological/Heritage) questions

[JoeSchmuckatelli]

Presuming a reasonable near future tech /space based logistical footprint that would allow for asteroid mining... 

1.  Would you have to stop the rotation of your target asteroid before mining?  (And if so, how could we do it?) 

2. What do we do with the tailings / slag?  (Would they likely aggregate or scatter - and if laws required keeping them in situ, how could we do that?) 

3.  From an economic perspective - would there be any reason to try to bring the ores back to Earth's surface, or would they be better used in further development of the space based economy? 

4.  Could you protect certain asteroids from mining - like Ceres, Vesta, etc - as a 'heritage site' - and if so, would you want to? 

5.  Do we know whether there is a higher metallicity in main belt or Jupiter Trojans?  (I.e. where are the best mining targets out there?) 

Presumes mining the material on site - not some stupid thing like trying to bring an asteroid back to Earth. 

Edited October 19, 2020 by JoeSchmuckatelli

[kerbiloid]

1. The rotation relative to stars or relative to Sun? Anyway, why stop it?

2. As there is no purppose in mining iron or empty to deliver it to the Earth, the aim would be platinoids/lantanoids/actinoids.
As they would be scattered with low concentration, the slag is "99.999%" of asteroid mass. So, probably they would literally turn it inside out.

Or they can heat the rock up to ionization temperature (and will probably do it, for brute force extraction of the desired chemical elements in absence of any available chemicals), then the whole body of the asteroid will be turned into metal dust  and gases, so they can just make metal plates out of rocks, and build storehouse structures or so.

3. Only platinoids/lantanoids/actinoids. The technologies required on asteroids could produce same resources on the Earth or even on the Moon much more productively.

4. I would predate small ones just to avoid thinking what to do about slug.
Also on the largest ones we need to go deeper, as they are hundreds of kilometers large. So, actually we could mine only their surface.

Edited October 19, 2020 by kerbiloid

[NFUN]

8 hours ago, JoeSchmuckatelli said:

Presuming a reasonable near future tech /space based logistical footprint that would allow for asteroid mining... 

1.  Would you have to stop the rotation of your target asteroid before mining?  (And if so, how could we do it?) 

2. What do we do with the tailings / slag?  (Would they likely aggregate or scatter - and if laws required keeping them in situ, how could we do that?) 

3.  From an economic perspective - would there be any reason to try to bring the ores back to Earth's surface, or would they be better used in further development of the space based economy? 

4.  Could you protect certain asteroids from mining - like Ceres, Vesta, etc - as a 'heritage site' - and if so, would you want to? 

5.  Do we know whether there is a higher metallicity in main belt or Jupiter Trojans?  (I.e. where are the best mining targets out there?) 

Presumes mining the material on site - not some stupid thing like trying to bring an asteroid back to Earth. 

1. no

2. leave it there, shoot it out of a cannon, get a baseball player to chuck fragments, whatever you like, who cares

3. presumably, as you get further in the future the need to bring them back to Earth will lessen

4. you "could", but you probably wouldn't want to (who cares?) and if you're really concerned, see 2

 

[Entropian]

11 hours ago, JoeSchmuckatelli said:

1.  Would you have to stop the rotation of your target asteroid before mining?  (And if so, how could we do it?)

I don't think so, and, in fact, I would think it would be detrimental to do so.  If it's spinning, you can just extend an arm above the surface, let go, and boom: the payload is in orbit.

11 hours ago, JoeSchmuckatelli said:

2. What do we do with the tailings / slag?  (Would they likely aggregate or scatter - and if laws required keeping them in situ, how could we do that?)

Use it as a radiation shield.

11 hours ago, JoeSchmuckatelli said:

3.  From an economic perspective - would there be any reason to try to bring the ores back to Earth's surface, or would they be better used in further development of the space based economy? 

Bring it back to Earth initially to get funding for your mining company, then eventually you can use the mined resources only for space-based things.

11 hours ago, JoeSchmuckatelli said:

4.  Could you protect certain asteroids from mining - like Ceres, Vesta, etc - as a 'heritage site' - and if so, would you want to? 

I don't see why you need a heritage site for a planet.  It's international waters, and what's so special that people need to preserve it?

11 hours ago, JoeSchmuckatelli said:

5.  Do we know whether there is a higher metallicity in main belt or Jupiter Trojans?  (I.e. where are the best mining targets out there?)

We don't know because no missions have been flown to the Trojans, although there's 1 funded mission (Lucy) and a proposed solar sail mission (JAXA).

[Spaceception]

13 hours ago, JoeSchmuckatelli said:

From an economic perspective - would there be any reason to try to bring the ores back to Earth's surface, or would they be better used in further development of the space based economy? 

To preface, I'm not an expert here, but this is what I've gathered, so I hope I didn't misunderstand something important.

I would say no to ores, but possibly yes to manufactured goods (depending on what it is, space computers?). In-space manufacturing could relieve a lot of resources on Earth used for rockets that could instead be dedicated to more personnel and spare equipment, rather than sending every single piece of equipment and resources needed to sustain them on top of that. There is likely a market to be made about recovering space junk, and repairing/returning satellites for ground customers. Not to mention robust space probes/telescopes that aren't nearly as volume or mass constrained.
SpaceX's Starship could do a lot to lower the cost enough to enable this, but even if it reaches its most aspirational goal ($2 million a flight, not including refueling), the marginal cost per kg would be $20. Skimming over google, looking at air freight, this drops to $5 or less. And I believe it can drop well under a dollar in other transportation, so you'd be paying a good amount more for the same product. And this isn't accounting for the cost of manufacturing or anything like that. Ground industry has a lot of lead here.

To be fair, there would be a lot of interest in buying things from space for the sake of it - or if you can simply afford it - but it won't be a major part of the economy unless rates dropped even lower to be competitive with ground transport of goods, and we began mass manufacturing for millions of people. So, not until we have things like O'Neil cylinders or so.

So while I would really like to see our economy become space-based, this won't be possible for a long time, and might require mega-projects such as orbital rings, or skyhooks.

Edited October 20, 2020 by Spaceception