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Comment by snewman | Hacker News Reader

Casey Handmer has a great blog taking hard analysis of what activities will be practical in space. He argues there is no real reason for asteroid mining to bring resources back to earth. So the challenge is to identify a large market for resources to be used in space.

https://caseyhandmer.wordpress.com/2019/08/27/there-are-no-k...

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So, the current price to bring something from space to Earth is for a capsule that keeps the material in a comfortable Earth-like atmosphere with minimal heating and g forces on the way down the way humans like it. If you instead have an object that doesn't need to breath and doesn't mind pulling 1000s of gs then things are much simpler, just take a reasonably sized sphere of your platinum ore, wrap it in some cheaper ablatable material, and drop it onto a desert then take it out of the small crater. Which isn't to say I actually think that asteroid mining for use on Earth is viable, just that the numbers used in that article are way too pessimistic.

In the short orbital communication is a >$100 billion a year industry and people are already looking at ways to manufacture larger antennas than can fit in rocket fairings in space for better signals. Even modest amounts of metal from an asteroid would be very valuable in orbit there since your competing with material that has to be brought up from Earth. Even bags of loose regolith could be very useful as radiation and meteorite protection.

Why not shaping it into some sort of lifting body, made out of honey comb like structures, and have that land into the ocean near the coast, to be towed to the next factory complex on land and disassamble the refined raw materials there? Combine with maybe inner compartments for standardized space containers for whatever else? This could be completely passive and autonomous, where the attached engine modules for deorbitng could detach and climb back up to some parking orbit or space dock before reentry happens. By choosing the right dimensions of that lifting body(surface to weight) you could avoid much of the reentry heat, down to about 400°C.

I was just talking about the minimal viable product. Yeah, metal foam is something you can make in space but not on Earth and it might be valuable to send metal down for that reason. Using a glider will increase uncertainty about where the results end up, though, compared to a simpler measure of decent. I think accepting some ablation as the price of accuracy is probably the way to go.

Honestly I don't think this would be a really big problem.

But to be absolutely sure nothing bad can ever happen(TM):

Why not have purpose built catching planes match up with them, once they are low and slow enough? I imagine something Airbus A380 sized, or large Antonovs, C5 Galaxy, releasing a clamp or hook on a cable or boom, connecting to that glider in the air. And tow it to its designated splash down area.

Like in https://en.wikipedia.org/wiki/Mid-air_retrieval

There! Solved that for you :)

Depends on if you put some control software on the glider. Generally a controllable aerodynamic shape gives you a good amount of cross-range ability to pick your landing ground, and a good amount of accuracy to land there with precision.

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