Joe_NoOne (48818) writes "NASA has achieved a breakthrough in space propulsion technology, albeit at a small experimental level. Researchers at the space agency have successfully tested the microwave thrusters that can work without any propellant. It was considered impossible because the propulsion system violates the law of conservation of momentum.
NASA said the electric propulsion device generated a force that is not attributable to any classical electromagnetic phenomena. The amount of thrust generated was only 30-50 MicroNewtons (mN), even less than the weight of an iPhone. But the fact that the system generated even a small amount of thrust without any onboard source of fuel clearly violates the law of conservation of momentum"
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