Editing Rocket (section)

===Propellant===
{{Main|Rocket propellant}}
[[File:Gas Core light bulb.png|thumb|left|Gas Core light bulb]]

Rocket propellant is mass that is stored, usually in some form of [[propellant]] tank or casing, prior to being used as the propulsive mass that is ejected from a [[rocket engine]] in the form of a [[fluid]] [[jet (fluid)|jet]] to produce [[thrust]].<ref name="RPE7"/> For chemical rockets often the propellants are a fuel such as [[liquid hydrogen]] or [[kerosene]] burned with an oxidizer such as [[liquid oxygen]] or [[nitric acid]] to produce large volumes of very hot gas. The oxidiser is either kept separate and mixed in the combustion chamber, or comes premixed, as with solid rockets.

Sometimes the propellant is not burned but still undergoes a chemical reaction, and can be a 'monopropellant' such as [[hydrazine]], [[nitrous oxide]] or [[hydrogen peroxide]] that can be [[catalyst|catalytically]] decomposed to hot gas.

Alternatively, an inert propellant can be used that can be externally heated, such as in [[steam rocket]], [[solar thermal rocket]] or [[nuclear thermal rocket]]s.<ref name="RPE7"/>

For smaller, low performance rockets such as [[attitude control thruster]]s where high performance is less necessary, a pressurised fluid is used as propellant that simply escapes the spacecraft through a propelling nozzle.<ref name="RPE7"/>