Questions tagged [hydrogen]
Questions about the element hydrogen, typically related to its use as rocket fuel.
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Hybrid combustion of ALICE with LOX?
I'm working on a sci-fi universe for a role-playing game and am wondering if a disposable short-distance rocket (most likely used in a cheap missile) could be optimized by adding liquid oxygen to the ...
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Is methalox actually any better than hydrolox? [duplicate]
I have been reading a lot about the fact that many SpaceX systems are using (or plan to use) methalox-burning engines, running on the reaction $\text{CH}_4+2\text{O}_2\to 2\text{H}_2\text{O}+\text{CO}...
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Will the last launch of the Delta rocket family cause changes to the liquid hydrogen supply chain?
This is a question from outside the StackExchange network that I'm reposting with permission from the original author. I honestly don't know if I think it's more likely to get answered here or on ...
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Why are nitric acid and hydrogen combinations not used as rocket fuel?
I was recently doing a chemistry assignment about bond energy when I noticed the incredibly low bond energy of nitric acid. Given the high bond energy of a nitrogen triple-bond, this set me wondering ...
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Hydrogen-propelled space elevator [closed]
I'm working on a space elevator design using kerosene-burning jet engines and dirigibles supporting 1km stages of pipeline and cable stretching up to the end of the stratosphere (~50km), then using ...
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ROFI Temperature
Since hydrogen-fueled rockets usually require Radial Outward Firing Igniters (ROFI), what is the temperature of the sparks from this system? When seen at RS-25/RS-68 ignition, they don't melt but ...
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Lunar nuclear power system - how can hydrogen generated on the Moon be liquefied?
In September 2020, NASA asked for proposals for a lunar nuclear power system.
The 10-kW water electrolysis system can create 5-10 tons of hydrogen in a week from the Moon’s surface ice.
How would you ...
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How does Titan have hydrogen in its atmosphere?
Titan's atmosphere contains few tenths of a percent of hydrogen.
This seems odd to me, as Earth with a 4x greater escape velocity cannot retain hydrogen or even helium in its atmosphere.
Titan is 3x ...
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Artemis H2 leak -- what is rationale behinfd 4% stated go/no-go parameter
The Artemis H2 leak has been quoted in %. I believe 4% is the stated limit. I assume that measurement is vol % of H2 in air but I haven't seen any real definition of the parameter. What is the ...
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Why is hydrolox used for first stages?
I understand that hydrolox has the highest specific impulse of any conventionally used propellant, but its density is so much lower that you would get more impulse in Newton seconds out of the same ...
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Why is monopropellant used?
The most efficent fuel, liquid hydrogen, is a bipropellant. So, why don't we just use bipropellants? Some monopropellants, such as hydrazine, are toxic. Wouldn't it be easier to just use bipropellants ...
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Do reversible proton-exchange membrane hydrolizer/fuel cells exist? Have they been incorporated into a “Hydrogen Battery”?
Solar power on the Moon suffers from the month-long Lunar rotation which necessitates enough energy storage to last through the 2 week Lunar night.
An alternative to battery storage would be a closed-...
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Can the cryogenic expansion of liquid oxygen and liquid hydrogen be used to pump a rocket engine?
A common fuel amongst rockets is that of the combination of cryogenic liquid hydrogen and liquid oxygen. I looked at the design of a simple rocket using this cocktail that is the propellant and found ...
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Is there believed to be sharp boundary between Jupiter's liquid and metallic hydrogen layers and is there much convection and flow between them?
If it's not known, is it reasonable to assume that some Jupiter-like exoplanets might have well separated liquid and metallic hydrogen layers given moderately different temperature and mass?
Author: ...
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Comparison of rocket engines using LH2 & LOX as propellants
I am a bit confused - If it is correct that RL 10 and LR 87-LH2 both were developed in 1950 by Aerojet, and both used LOX and LH2 as the propellants, if so, then why was there a huge difference in ...
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