NASA approved an "impossible" space engine design in a recent paper published by the agency's experimental Eagleworks Laboratories. NASA engineers confirmed in the paper that they produced small amounts of thrust from an engine without propellant.
The discovery is an apparent violation of the conservation of momentum, which states that every action must have an equal and opposite reaction. The Independent notes that the supposedly impossible engine could revolutionize space travel.
Traditional spacecraft must carry massive amounts of fuel with them in order to move around. They use the thrust created by this fuel to move in zero gravity. While the method works just fine, it is costly both to obtain the fuel and to launch the extra weight into space.
The space propulsion technology uses a microwave thruster system that requires no propellant. The engine, known as the "Cannae Drive," uses electricity to generate microwaves. These waves bounce around inside a specially designed container that should theoretically create a difference in radiation pressure, resulting in directional thrust.
In a normal engine, the rocket moves forward when fuel is flung backwards. The momentum of the rocket is "conserved" because it is moved from the rocket to the fuel. However, NASA's "impossible" engine has no fuel and the microwaves aren't expelled from the engine.
News of the space engine design's success was first reported by Wired UK, which noted that British scientist Roger Shawyer has been trying to interest people in the EmDrive for several years. He has built several demonstration systems, but critics reject his theory and insist that it can't work, because of the law of conservation of momentum.
A Chinese team already built its own EmDrive and confirmed it produced about 72 grams of thrust. That amount is enough for a practical satellite thruster, but not an entire space ship. A thruster like this could be powered by solar electricity, eliminating the need for the supply of propellant that accounts for nearly have the launch mass of many satellites.
The Chinese work gained little attention until NASA tested out the electromagnetic engine built by U.S. scientist Guido Fetta. Five researchers spent six days setting up test equipment and two days experimenting on the impossible space engine with various configurations.
The drive tested by NASA produced 30 to 50 micronewtons -- less than a thousandth of the Chinese results, but still a positive result.
Further experiments are expected to confirm the reality that NASA's "impossible" space engine may actually work.