Questions tagged [chemistry]
Questions regarding the application of chemistry in space exploration, for example the composition of rocket propellants.
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What is the dark brown gas emission seen during the ascent of Starship?
During the video (see below) of Starship IFT-4 there is a lot of brown smoke or gas in the Superheavy exhaust from near the start for almost 30 seconds. Is this NO2? If so roughly how much is produced?...
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What is the ratio of air and ethyl alcohol that must be in order to power a rocket engine? [closed]
There is a rocket engine that will run on a fuel pair: air + ethyl alcohol, but what percentage of components should be supplied ...
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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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What is the prevalence of nitrogen, phosphorus, and potassium in the asteroid belt and in comets?
As someone with a light background in controlled-environment agriculture, I'm familiar with the importance and use of N/P/K in growing useful plants. This got me thinking about how common these ...
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Interpretation of mars rover images
I’ve been obsessed with the perseverance images, specially the images from the SHERLOC-WATSON system- the UV camera tricked out with racing stripes and fuzzy dice hanging from its rear-view mirror (...
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Are there any gaseous monopropellants?
There are numerous liquid monopropellants: Hydrazine, Hydrogen Peroxide, Nitrous Oxide, Isopropyl Nitrate, and more.
There are of course also solid monopropellants. (Edit: composite propellants not ...
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Chemical Problems When Encountering Thin Atmospheric Worlds
Bodies such as Enceladus, Mercury, and Triton, etc... have thin (and often temporary) atmospheres.
When probes or landers encounter the chemicals in such atmospheres in low orbits/landings, they may ...
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If a spacecraft's double hull filled with water is hit by a micrometeorite, could the water freezing or surface tension stop the leak?
I'm thinking about the possibilities of water storage also serving radiation shielding for long space journeys (months to years).
Assume within the solar system but outside of upper earth orbit. ...
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NTR performance of hydrazine compared to ammonia?
Methane, ammonia and water are sometimes suggested as alternatives to hydrogen for a nuclear thermal rocket.
While they have a lower specific impulse, they offer much better density, thrust, and ...
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Important new additives to hypergolic hydrazine-based fuels since 1972?
In "Ignition! An Informal History of Liquid Rocket Propellants", John D. Clark in one of the chapters gives an overview of the then current state of hydrazine and hydrazine derivatives.
The ...
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What is the cause of soot in the plume of the Raptor engine?
Though the Raptor engine burns quite clean, it was clear from some early test flights that it did produce some visible soot:
There have been differing explanations for the exact cause of/source of ...
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What am I missing about rocket nozzle isentropic flow?
Playing a bit with Cpropep-Web, something looked wrong to me about how it models isentropic flow through a CD nozzle.
I'm taking the RS-25 characteristics as an example. I ask for a frozen equilibrium ...
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How much solar radiation hits a spacecraft in transit to Mars?
How can I solve for the amount of radiation that hits a Mars transit vehicle, in transit? What formulas should I use? I am mostly focused on solar radiation.
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Why do $\text{CH}_4$ (Raptor) engines produce less soot than RP-1 (Merlin) engines?
SpaceX's Merlin engine, which burns RP-1 and LOX, has soot visible after the first stage lands. Many articles on the web say SpaceX's Raptor engine, which burns methane and LOX, is clean. ...
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Can the higher oxides of nitrogen, like nitrogen pentoxide, be used as oxidisers in rocket engines?
Both nitrous oxide (N2O) and dinitrogen tetroxide (N2O4) are used in storable propellant combinations, so, simply as a continuation, can the higher oxides of nitrogen (N2O5, N2O6, etc.) still be used ...
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