Why do we not use nuclear energy to roam about in space and go the distance if it lasts long and needs minimum refueling?

Question

Why do we not use nuclear energy to roam about in space and go the distance if it lasts long and needs minimum refueling?

In: 4

Answer 1

We do; Voyager-1 and -2 for example are powered by [Radioisotope thermometric generators.](https://en.wikipedia.org/wiki/Radioisotope_thermoelectric_generator#Space) This type of nuclear power source harnesses the energy of decaying radioactive atomic nuclei by converting the heat generated directly to electricity. They don’t use fission like land-based nuclear power plants because a fission reactor is very big and heavy and would be hard to get into orbit.