We have known how to build working NTRs since before the moon landings. They are a proven technology but we decided is was not worth the risk to fly them.
What changed? Or will this rocket stay firmly on the ground?
What changed? Or will this rocket stay firmly on the ground?
Technology can just progress, nothing massive needs to change. DARPA sees that the time is ready to advance this technology once again. They will test it first at very small scale. The purpose is deep space space force robotic vehicles being able to make lots of maneuvers (to avoid ASAT? To do multiple missions? Changing orbit to avoid detection?) with high thrust, ie quickly.