Sunday, March 18, 2012
The smallest orion, a 10 meter NASA prototype, would have been useful for manned missions to the planets. Initially it would be great for a Mars return trip, carrying tons of payload and arriving quickly. A modified or slightly larger orion would have been suitable for return trips to and from the Jovian Planets. Larger rockets still could carry permanent bases, or astronauts in style. The largest orion craft would be able to fly small cities. These would be ideal generation ships, slowly traveling to other star systems. Only the largest orion spacecraft could make a practical, single generation trip to a local star. These would have to be extremely large, the size of a real city, and be of the "thermal" type where forward thrust is generated by the absorption and re-radiation of photons from large radiation implosion type bombs.