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Old 01-22-2018, 03:22 PM   #867 (permalink)
sendler
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Join Date: May 2011
Location: Syracuse, NY USA
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Honda CBR250R FI Single - '11 Honda CBR250R
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2001 Honda Insight stick - '01 Honda Insight manual
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Quote:
Originally Posted by redpoint5 View Post
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.
it takes more energy to slow down and come back than to slingshot Mars to get to the belt. For what? A couple hundred kg's of metal?
These guys are talking about decelerating an entire asteroid all the way back to Earth orbit and then mining nickle and iron. Can't happen. Even at our current peak energy availability. In a matter of decades all of the energy we can get our hands on will be tied up in just trying to grow enough food and get clean water and sanitation for a ballooning population. And feverishly applied to replacing the fossil fuel that will be slipping away. If we are smart. Nothing left over to play with sending humans out into space after that. Ever again.