of energy and heat at high speeds, which propels the spacecraft forward. This happens due to one basic principle known as Newton's third law. According to Newton, "to every action there is an equal and opposite reaction." As the energy and heat is being released from the back of the spacecraft, gas particles are pushed that allow the spacecraft to propel forward. The main reason behind the use of rocket engines today is because rockets are the most powerful form of propulsion.

Monopropellant