The Project Orion people had extensive calculations on how to send a city-sized ship to another star on a ~100 years trip with nukes.
It is laser propulsion that is techno-magic. Even today. I won't register on whatever site to read yet another article on that, but I do bet neither the lasers nor the sail on this one could be made today.
It is laser propulsion that is techno-magic. Even today. I won't register on whatever site to read yet another article on that, but I do bet neither the lasers nor the sail on this one could be made today.