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is expected to be launched. The problem with basing the design on current hardware is one of weight and speed. Producing a system with the required intelligence and speed, while including the needed redundancy using current technology, would result in a huge unit requiring a cooling system as large as a nuclear power plant's. Current advances have shrunk a Cray 2 from a room sized system needing a huge cooling plant to two chips, and with the advent of high temperature super-conductor technology there is every reason to assume that many more such quantum leaps in computer technology may be expected in the next 20 to 30 years.
Since no one has ever designed a dynamic system to last for more than a century, it is impossible to guess just how much the reliability of current systems will have to be improved. However, many satellites which were designed with mission lives of only a few years have operated for much longer periods of time, often failing merely because they ran out of expendables. The Transit family is a good example: they were designed to last for only 18 months and there are some still operating after 18 years or more. Other examples include Pioneer, Mariner, Voyager, and Viking. With successes in reliability such as these, and the improvements in simulation technology which will come with the improvements in computer technology (discussed in the previous paragraph), there should be no difficulty in designing in the required reliability.
