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Great article on the history and discovery of the actinide elements. The astronauts lives were apparently saved by the warm Plutonium battery powering the Luna

Great article on the history and discovery of the actinide elements. The astronauts lives were apparently saved by the warm Plutonium battery powering the Lunar Module's scientific equipment (not exactly sure how though). EDIT: I know what Radioisotope Thermoelectric Generators are, but not why the warm battery saved Apollo 13.

gh02t 12y ago
Not sure how it generates power? Pu238 is a very strong alpha emitter. Alpha particles (helium nuclei) are really big and charged, so they don't travel very far and deposit all their energy near where the decay occurs (as opposed to decay with e.g. neutrinos that essentially never interact and thus deposit no energy). The alpha decay carries a lot of energy so a chunk of Pu238 gets pretty hot. Couple it with a thermoelectric generator and you have an ideal power source for space applications. Also, alpha particles have almost no penetrative power in human tissue so they're harmless as long as the source isn't inside of you. Pu238 is almost exclusively an alpha emitter, so it's completely safe to handle for extended periods, at least radiologically. It puts off a ton of heat and is chemically really toxic though. I've dealt with it in the lab before, it's relatively harmless as far as nuclear sources go. It's not suited for weapons either, so it isn't directly a proliferation concern, though producing it is because it is related to weapons grade production. You don't see it used very often mostly because it can only be made in a specially configured reactor, so it's not exactly common.
- tunnuz 12y ago
  Thanks for the power generation explanation.
colechristensen 12y ago
Thermoelectric generators are dead simple means of reliably generating a small amount of power for a very long time without moving parts. What you do is get a lump of radioactive material and stick a bunch of thermocouples around it. The lump of radioactivity stays hot because it's radioactive, and the thermocouples produce a very low efficiency amount of power out of the temperature difference. http://en.wikipedia.org/wiki/Radioisotope_thermoelectric_generator http://en.wikipedia.org/wiki/Radioisotope_thermoelectric_gen...

gh02t 12y ago

Not sure how it generates power? Pu238 is a very strong alpha emitter. Alpha particles (helium nuclei) are really big and charged, so they don't travel very far and deposit all their energy near where the decay occurs (as opposed to decay with e.g. neutrinos that essentially never interact and thus deposit no energy). The alpha decay carries a lot of energy so a chunk of Pu238 gets pretty hot. Couple it with a thermoelectric generator and you have an ideal power source for space applications. Also, alpha particles have almost no penetrative power in human tissue so they're harmless as long as the source isn't inside of you. Pu238 is almost exclusively an alpha emitter, so it's completely safe to handle for extended periods, at least radiologically. It puts off a ton of heat and is chemically really toxic though. I've dealt with it in the lab before, it's relatively harmless as far as nuclear sources go. It's not suited for weapons either, so it isn't directly a proliferation concern, though producing it is because it is related to weapons grade production. You don't see it used very often mostly because it can only be made in a specially configured reactor, so it's not exactly common.

tunnuz 12y ago
Thanks for the power generation explanation.

colechristensen 12y ago

Thermoelectric generators are dead simple means of reliably generating a small amount of power for a very long time without moving parts. What you do is get a lump of radioactive material and stick a bunch of thermocouples around it. The lump of radioactivity stays hot because it's radioactive, and the thermocouples produce a very low efficiency amount of power out of the temperature difference. http://en.wikipedia.org/wiki/Radioisotope_thermoelectric_generator http://en.wikipedia.org/wiki/Radioisotope_thermoelectric_gen...