But by the '60s the ICBM had become routinized as the delivery vehicle for nuclear warheads and everyone realized that super-fast interceptors (and supersonic bombers) were kind of pointless.

The unmanned space vehicle — inspired by nuclear pulse propulsion studies by the British Interplanetary Society in the 1970s — will ideally reach its target star within 100 years after launch.

The ship is the first in the scale of increasing vehicle size that would appear to be adaptable to nuclear power.