Re:Why I thought we'd all be living in space by now
by gaius on Sunday January 11, 2009 @05:53PM
(#429767)
Powered re-entries to Earth are not feasible and not desirable
If you've just mined a million tons of iron from an asteroid, I think you would want to bring it back in a controlled fashion!
Re:Why I thought we'd all be living in space by now
by gravitycop on Sunday January 11, 2009 @05:58PM
(#429776)
Do you consider the Apollo or Soyuz re-entries to be too uncontrolled?
That is what the Sea Dragon is for. The payload capacity is 1.2 million pounds, and can be expanded with minor modifications.
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It's only expensive and difficult now because we don't have anything with enough energy density to do it.
We have kerosene and liquid oxygen. Chilled propane works, too. Are you thinking that these fuels and oxidizers are somehow not adequate? If so, in what way?
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If you can make a powered re-entry you don't even need to bother with the Shuttle's elaborate heat shielding
The Shuttle requires elaborate heat shielding for reasons that have nothing to do with the fact that it does not make powered re-entries. The Russian Soyuz capsule re-enters with a basic heatshield and lands on the Kazakh steppes. It's cheap. It's reliable.
Powered re-entries to Earth are not feasible and not desirable. They would be outrageously expensive and probably unreliable (read: dangerous).