Project Orion was a study of a spacecraft intended to be directly propelled by a series of explosions of atomic bombs behind the craft (nuclear pulse propulsion). Early versions of this vehicle were proposed to have taken off from the ground with significant associated nuclear fallout; later versions were presented for use only in space.
–which, yea, sounds pretty patently nuts. But keep reading, and it begins to look *really* attractive:
The Orion concept offered high thrust and high specific impulse, or propellant efficiency, at the same time. The unprecedented extreme power requirements for doing so would be met by nuclear explosions, of such power relative to the vehicle’s mass as to be survived only by using external detonations without attempting to contain them in internal structures. As a qualitative comparison, traditional chemical rockets—such as the Saturn V that took the Apollo program to the Moon—produce high thrust with low specific impulse, whereas electric ion engines produce a small amount of thrust very efficiently. Orion would have offered performance greater than the most advanced conventional or nuclear rocket engines then under consideration. Supporters of Project Orion felt that it had potential for cheap interplanetary travel, but it lost political approval over concerns with fallout from its propulsion.
They actually made demo prototypes of this bomb-drive, in order to convince government backers that it was *less* nuts than it sounded, and it does indeed looks pretty rad: Project Orion: “To Mars by A-Bomb” RARE Footage – YouTube
Anyway, if this lil sidebar in the history of the atomic bomb tickled your fancy, then you can do worse then losing a few hours sifting through Alex Wellerstein’s Restricted Data blog. Start here: The “Secret” song | Restricted Data
