A common misconception is that rockets push against the air or the ground. In reality, rockets work on Newton’s Third Law: for every action, there is an equal and opposite reaction. High-pressure liquid oxygen and liquid methane or kerosene react violently in the combustion chamber at over 3,000°C. The bell nozzle funnels and accelerates this gas to supersonic speeds. As billions of gas particles are ejected downward at 3,500 m/s, the vehicle is propelled upward with massive forward momentum.