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Old 01-22-2018, 01:17 PM   #866 (permalink)
redpoint5
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Quote:
Originally Posted by sendler View Post
anyone that runs the numbers will easily see that the energy required for harvesting an asteroid and bringing it back to earth orbit falls squarely past won't happen into the category of can't happen.

What is the total sum of mass we ever brought back from the moon? Which is several orders of magnitude energetically closer than the asteroids.
Having not run any calculations, it might take less energy to visit an asteroid and return than to visit the moon and return. A moon landing requires accelerating to it, stopping on it, and then accelerating back to earth. An asteroid rendezvous can conserve the majority of the momentum used to get there, and there is practically no gravity to overcome to leave it. If it were rich in expensive elements such as gold or platinum, it could be economically worthwhile.

That said, I agree with your sentiments that the resources we regularly consume in bulk aren't going to be replenished by asteroids.

We'll get better at reusing materials, and possibly creating new materials out of other other ones.
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