[sci.space] Plutonium-power for space craft .. how ?

tony@yunexus.UUCP (Tony Wallis) (09/18/89)

(Sorry if this has been covered in sci.space or sci.space.shuttle.
 I do read sci.physics and sci.energy regularly.)

There are media reports of attempts to legally halt the launch of
Galileo on the grounds that it contains many kilos of Pu in its
power source, and should there be a launch accident there would be
lots of plute all over the place etc. etc. 

Other reports emphasize that there is NOT a nuclear REACTOR on board
Galileo.

So .. *physics* question : how do you use many kilos of Pu to provide
power at space craft levels without using a self-sustaining fission
chain-reaction ?

Follow-ups to sci.physics

--
Tony Wallis   tony@yunexus.UUCP    (York U.  Toronto  Canada)

tony@yunexus.UUCP (Tony Wallis) (09/20/89)

Thanks to the many people who e-mailed me the answer.
Heat from radio-isotope decay and thermo-couples.  No moving parts.

Actually, I had thought of that - but although I knew Pu was warm (warm
enough to make the oxide "creep") I didn't know it was that hot.
Significant contribution from isotopes with shorter half lives than
Pu-239 ?