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I understand that the asteroid mining proposals are looking to mine platinum, paladium, and other rare-earth metals that have a high economic value. What are the proposals for getting the mined material back to earth in an economic manner?
It seems to me it would be cheap if they could some 'drop' the material back, but of course, they need to avoid disasters and make sure its retrievable. Controlled returning, such as on a spacecraft, would add to the cost.
Are there compromise options, such as manufacturing the material into a 'glider' that can go to safely to the Earth in a controlled, inexpensive manner?