1.   The decision ends British involvement in the development of fast-breeder reactors, which unlike conventional reactors breed their own plutonium fuel.

2.   Age is an issue now because the Energy Department is no longer turning out new warheads or new plutonium fuel to replace the existing stock.

3.   But no reactors are currently licensed to be loaded with plutonium fuel, and obtaining the necessary permits would almost certainly be politically troublesome.

4.   Notwithstanding barriers to development now in place, he said, plutonium fuel and the substantial hazards that accompany nuclear energy may become major concerns in the state.

5.   Other opponents who consider that loading plutonium into a spacecraft is folly contend that plutonium fuel is unnecessary, noting that other planetary missions have successfully used solar batteries.

6.   RTGs convert the heat from decaying plutonium fuel into electricity.

7.   Plutonium fuel can be extracted from the waste of other types of reactors.

8.   Critics say shutting down Monju causes stockpiling of plutonium fuel.

9.   Fast-breeder reactors generate more plutonium fuel than they consume.

10.   It was built to burn used fuel, transform it to new plutonium fuel and produce electricity.