On 12/9/2018 5:07 PM, Bruce Farquhar wrote:
On Sun, 09 Dec 2018 21:40:03 -0000, Rod Speed
wrote:

Bruce Farquhar wrote

A thermocouple produces enough to power a spacecraft?!?

It isnt a single thermocouple, it's a thermopile.
https://en.wikipedia.org/wiki/Thermopile
https://en.wikipedia.org/wiki/Nuclear_power_in_space

Or just for some small electronics?

Not small at all.

Why are these not used on earth?
....

They are...and have been for 40 yr or more in remote locations like the
Arctic, Antarctic, lighthouses, etc., etc., ... the Russians probably
have had the most numerically but they've no monopoly.

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