How do conventional rockets work?
A monopropellant is a chemical propulsion fuel which does not require a separate oxidizer. A rocket engine which is based on a monopropellant requires only one fuel line instead of a fuel and an oxidizer line. The "mono" in monopropellant means singular--a fuel that can function alone. A chemical propulsion system that combines like hydrogen and oxygen would be a bipropellant. A monopropellant burns by itself because the oxidizer is bound into the molecule itself. This makes the rocket engine lighter, less expensive, and more reliable. Monopropellant designs are typically used in control thrusters but not in actual propulsion units.
What is a propellant?
How does propulsion work?
What are the types of rocket propulsion?
What is an oxidizer?
What kind of fuel do DS1's attitude thrusters use, and how much of it do they use?
What is chemical propulsion?
What would happen if DS1 ran out of fuel?
What are some rocket propellants?
What is hydrazine?