The Role of Thrusters in Space Systems

Spacecrafts, such as artificial satellites and space probes have small rockets called thrusters for orbital maneuvering, and satellite attitude control. These thrusters produce thrust by exhausting gases from their nozzles. On the other hand, reduction of propellant consumption, operability improvement/safer handling, and cost reduction are required for thrusters used. For this reason, reactive control systems use new propellants (green propellants) rather than toxic propellants. Various types of green propellants have been produced, which have not been used for various reasons, such as: low storability, low ISP, and  low density. However, operational characteristics of some types of green propellants are suitable to use. Hydrogen Peroxide, Nitrous Oxide, Hydroxyl Ammonium Nitrate, Hydrazine Nitroformate, and Ammonium Dinitramide are green propellants that are approved by many organizations and are beeing used in space thrusters. With a brief overview of types of thrusters, this article compares different green propellants and suggests the best option.