It's a Rotating Detonation Rocket Engine"
What makes the RDRE so revolutionary is that it makes use of a sustained detonation circling around a ring-shaped channel, fed by a mix of fuel and oxygen which is ignited by each passing explosion.
Crucially, the RDRE uses less propellant fuel than conventional rocket engines, and is simpler in terms of its machinery and mechanisms. That means going into space becomes cheaper, and traveling further distances becomes possible.
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