Abstract
Antimatter possesses a highly condensed energy and the mass is completely converted to the energy by an annihilation reaction with matter. It has been considered as a science fiction that the space mission using such great amount of energy to other stars within the working lifetime of the crew.
The p-p annihilation engine has been studied mainly in Europe and U.S.A.
The reactor size is not so different from the main engine of Space-shuttle. At the present moment the antiproton is produced with use of a huge accelerator. In future, however, the optimization of production facilities enables the economical use of antiproton for a space vehicle. Nevertheless only a milligram of antiproton has energy of several-ten times as much as the conventional fuel.
