Questions tagged [fuel]
Questions about rocket oxidizer, propellant, reactive mass, or other fuels used in spacecraft or rockets.
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What was used to lift the Apollo capsule off the moon and how come it took less energy to get back to earth
It took tons of fuel to leave earth from gravity and the speed of which it spins and travels thru space, big tanks of fuel and jet packs to direct it to the moon why it didn't need all that to return ...
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Use of NaK as a possible bipropellant/tripropellant rocket fuel?
Recently I asked this question about tripropellant rocket engines. In an effort to avoid dealing with hot molten metal or powdered metal as the additive, I turned to NaK as a possible solution.
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Feasibility of lithium or aluminum as a tripropellant liner for ablatively-cooled engines?
Studies have been previously conducted on the feasibility of using metal powder as a tripropellant in rocket engines (i.e. lithium/fluorine/hydrogen or aluminum/hydrolox). For example, this NASA study ...
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Space Shuttle and External Fuel Tank [duplicate]
I’ve often wondered how the Orbiter and the External Fuel Tank were held together. The attachment points seem awfully small to have enough strength to keep them together without having them tear apart....
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How (in)efficient would a rocket be that flew to orbital heights, hovered for a while, and then fell back down instead of going into orbit and back?
I understand in a vague and not mathematically rigorous way that most of the energy required to get a spacecraft into orbit goes into gaining "forward" speed, not actually in gaining ...
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How does one make propellant from recycled space junk?
While Burn 1st stage structural material as fuel? asks about a spacecraft consuming itself, inspired by the Monty Python poem "Horace", yhis question is inspired by recent news about a ...
user12102
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Is used propellant dangerous for other spacecraft, and if so, for how long?
Does the exhausted propellant of space probes pose a danger - as a cloud of high velocity particles - to other spacecraft crossing it soon after, or does it diffuse quickly enough in the vacuum to not ...
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Calculate distance from destination at which to commence deceleration burn
For a vessel with insufficient fuel to burn for the entire duration of an interstellar journey, how do you calculate when to commence the deceleration burn?
Using this answer I can calculate the fuel ...
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Could rocket exhaust eventually lead to detrimental effects from interplanetary space pollution?
I am interested in if the exhaust from a rocket would lead to space pollution like space junk does. Particularly, I am talking about the exhaust that stays in interplanetary orbit and does not return ...
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Why must LH2 be gassified before the throat in order to accommodate the high heat fluxes in regenerative cooled nozzles?
In NASA Space Vehicle Design Criteria Liquid Rocket Engine Fluid Cooled Combustion Chambers 2.1.1.2 number of passes (page 10) describes that some coolants must be heated before they become effective. ...
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Pyrolysis of regolith can produce hydrogen and oxygen. Is this a viable alternative to water hydrolysis for production of lunar H2/O2 propellant?
With the currently proposed lunar polar landings, there has been speculation about electrolysis of water for the production of hydrogen and oxygen for propellant. Electrolysis requires generous ...
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What are the challenges associated with using lithium hydride as a rocket fuel?
Setting aside issues of cost and toxic exhaust products, what are the difficulties of using LiH in a rocket engine? Is it corrosive?
Related question here:
https://chemistry.stackexchange.com/...
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How to account for the mass of solid propellant lost when measuring the thrust produced in Newtons?
I've had some confusion on how to calculate the mass-lost during the burning of solid-propellant $\require{mhchem} \ce{(C_{12} H_{22} O_{11} + KNO_3)}$ throughout the time interval of the burning. ...
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What is the optimum lunar latitude for a solar farm and hydrolysis plant?
What is the optimum lunar latitude for a solar farm and hydrolysis plant?
Water is hypothesized to be present at the lunar poles. There have been proposals to hydrolyzed it into propellant. Large ...
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Does SpaceX Starship have significant methane emissions?
SpaceX Starship apparently uses liquid methane and liquid oxygen as its fuel. Liquid methane is not ideal for its environmental problems (burning it creates CO2 which can't be captured from a rocket, ...
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