A variant of Orion was explored by the British Interplanetary Society, known
as Daedalus, was explored in the 1970s. Daedalus was to be an unmanned
interstellar vehicle that would be propelled by “fusion pellets” consisting of
deuterium and helium 3, ignited by electron beams in a combustion chamber. This
method of propulsion was far more elegant and efficient than the brute force
method of Orion. The concept, of course, could be adapted for manned
interplanetary voyages.
Fallout Problems
One of the unsolved problems of Orion was that of fall out resulting from a
surface launch. It was estimated that between one and ten people would die a
premature death from cancer for every surface launch of an Orion ship. Also,
were an Orion to be launched in the present, the electromagnetic pulse (EMP) of
the nuclear explosives would fry modern communications and computers for
hundreds of miles away. The solution would seem to be to assemble an Orion ship
in a high, “nuclear safe” Earth orbit and launch it to interplanetary
destinations from there.
Orion in Science Fiction
Naturally the idea of an Orion ship has found its way into science fiction.
Jerry Pournelle and Larry Niven, in their novel Footfall, imagined the building
of an Orion ship as a means to stave off an alien invasion of the Earth. Poul
Anderson, in his novel Orion Shall Rise, also imagined an Orion ship. Even the
film Deep Impact depicted an Orion ship being used to deliver a crew to a rogue
comet that threatened to destroy the Earth.