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A comment on SpaceX to Send Privately Crewed Dragon Spacecraft Beyond the Moon Next Year. Parent comment

Re:SpaceX to Send Privately Crewed Dragon Spacecraft Beyond ... by imglorp on Tuesday February 28, 2017 @07:35AM (#13753284)
That's a good question. A big bag of fuel hanging outside is a fine place to store it if you don't care about temperature or pressure. You would need some kind of mechanical means to squish the bag to get the fuel out though, so maybe an accordion with a motorized retractor?
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Re:SpaceX to Send Privately Crewed Dragon Spacecraft Beyond ... by robryk on Tuesday February 28, 2017 @12:02PM (#13755202)
I think you are underestimating expansion ratios (ratio of volume of liquid and gas at reasonable pressure). The ratio for water vapour at sea level is ~1000x. The "large bag" might end up being so large that it's weight is a significant fraction of the weight of the fuel it contains.
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Re:SpaceX to Send Privately Crewed Dragon Spacecraft Beyond ... by gozur88 on Tuesday February 28, 2017 @06:39PM (#13759402)
Even if you brought up a bag large enough to contain gaseous fuel and oxydizer, before you could actuall use the fuel you'd have to compress it again.
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