Hybrid propellant is a type of rocket fuel that combines two different states of matter: a solid fuel and a liquid oxidizer. The solid fuel is typically made from materials like rubber or plastic, while the liquid oxidizer, such as liquid oxygen or nitrous oxide, helps the fuel burn more efficiently. This combination allows for better control of the thrust and burn rate compared to traditional solid or liquid propellants. One of the main advantages of hybrid propellants is their safety and simplicity. They are less volatile than liquid fuels, reducing the risk of accidental explosions. Additionally, hybrid systems can be easier to handle and store, making them an attractive option for companies like SpaceX and Virgin Galactic that are developing new space launch technologies.