NASA and the Department of Energy have completed tests on several fission surface power components within the last few weeks. The agencies are researching technologies that could enable possible use of nuclear power on the surface of the moon and Mars. Nuclear power is part of the range of options that are being examined for potential human missions on the moon and Mars.

This is great news because we can put it on deep space probes too.

NASA and DOE Make Progress on Surface Nuclear Fission Power Technology | SpaceRef - Your Space Reference