On: Space Elevator

[actionfromafar]

Why is the water bad?

[pfdietz → actionfromafar]

In the stratosphere it both contributes to IR opacity, increasing global warming, and can provide ice surfaces on which ozone destruction is amplified. The stratosphere is normally extremely dry, so even small inputs can have an effect that would be invisible in the much moister troposphere.

[actionfromafar → pfdietz]

Aha, so in the stratosphere we should use oxygen / solid carbon boosters?

[pfdietz → actionfromafar]

Their Isp is very low, unfortunately, because the molecular weight of the combustion gas is too high. Ditto for oxygen/carbon monoxide.

Maybe the Isp could be increased by mixing in some helium, but helium is very expensive.

[LargoLasskhyfv → pfdietz]

Methalox should suffice for practical and technical reasons?

Compensate the slight loss of ISP by using aerospiked rotating detonation engines...

[pfdietz → LargoLasskhyfv]

Methalox contains hydrogen (methane is CH4), which turns into water, either in the engine, or oxidized by the atmosphere after being expelled.

[tonyhart7 → actionfromafar]

heavy as fuck

[actionfromafar → tonyhart7]

It would like, rain down hard?