Space technology is an investment into the future. Today's areas of activity, such as geo-observation, satellite communication, microgravitation, astrophysics, and astronomy already indicate that the investments made over a period of three decades into the development and operation of space systems already pay off. European launchers of the Ariane type are not only economic, but also guarantee political independence. Space technology is a cultural phenomenon, and man in space is a symbol standing for the transgression of all limits. Space technology needs nuclear power to solve its future problems. Manned space flight to Mars is hardly feasible without nuclear propulsion, and orbital nuclear power plants will be necessary to supply power to large satellites or large space stations. Nuclear power also needs space technology. A nuclear power plant sited on the moon is not going to upset anybody, because of the high natural background radiation level existing there, and could contribute to terrestrial power supply.