Editing CubeSat (section)

==== Chemical propulsion ====
[[Rocket engine|Chemical propulsion]] systems use a chemical reaction to produce a high-pressure, high-temperature gas that accelerates out of a [[Propelling nozzle|nozzle]]. Chemical propellant can be liquid, solid or a hybrid of both. Liquid propellants can be a [[Monopropellant rocket|monopropellant]] passed through a [[catalyst]], or [[Liquid-propellant rocket|bipropellant]] which [[Combustion|combusts]] an [[Oxidizing agent|oxidizer]] and a [[fuel]]. The benefits of [[Monopropellant rocket|monopropellants]] are relatively low-complexity/high-thrust output, low power requirements, and high reliability. Monopropellant motors tend to have high thrust while remaining comparatively simple, which also provides high reliability. These motors are practical for CubeSats due to their low power requirements and because their simplicity allows them to be very small. Small [[hydrazine]] fueled motors have been developed,<ref name=":0">{{Cite web| url=http://www.rocket.com/cubesat| title=Aerojet CubeSat Thrusters| access-date=September 4, 2015| website=Aerojet Rocketdyne| archive-url=https://web.archive.org/web/20150823030523/http://www.rocket.com/cubesat| archive-date=August 23, 2015| url-status=dead}}</ref> but may require a waiver to fly due to restrictions on hazardous chemicals set forth in the CubeSat Design Specification.<ref name="specs" /> Safer chemical propellants which would not require hazardous chemical waivers are being developed, such as AF-M315 ([[hydroxylammonium nitrate]]) for which motors are being or have been designed.<ref name=":0" /><ref>{{Cite web |url=http://busek.com/technologies__greenmonoprop.htm |title=Busek Green monopropellant thruster |access-date=September 4, 2015 |website=Busek Space Propulsion |publisher=Busek}}</ref> A "Water Electrolysis Thruster" is technically a chemical propulsion system, as it burns [[hydrogen]] and [[oxygen]] which it generates by on-orbit [[electrolysis of water]].<ref name="Tethers2015">{{cite web |url=http://www.tethers.com/HYDROS.html |title=HYDROS – Water Electrolysis Thruster |work=Tethers Unlimited, Inc. |date=2015 |access-date=2015-06-10}}</ref>