Richardc10

The fuel core for the SNAP-27 generator was stored on the _outside_ of the LM descent stage. It was installed into the generator by the astronauts on the lunar surface. I have chopped an image and some text from the Apollo 13 press kit.

https://www.dropbox.com/s/02px58fhbz0gigt/apollo13.pdf?dl=0

I doubt there would have been much thermal path from the fuel element back into the LM itself - indeed the mount would probably have been designed to minimise that flow since the problem is normally how to reject heat from a spacecraft, rather than absorb it. The story just seems a tag to discuss plutonium.