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PostPosted: Jul 13, 2010 7:56 pm 
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This is pathetic..... more exporting of American skills overseas....

Nuclear-Challenged U.S. Turns to Europe to Meet NASA's Plutonium needs
Jason Mick (Blog) - July 12, 2010 10:41 AM

Image

An ingot of Plutonium-238, the typical power source used by NASA for its probes. (Source: Discovery News)

Europe, a leader in nuclear power, has announced that it intends to lend its American counterparts a hand by making Pu-238 for NASA. David Southwood, ESA's director of science and robotic exploration, in an interview with Spaceflight Now, states, "Our target is to have an independent capability, which may help our American friends."
<SNIP>


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PostPosted: Jul 13, 2010 8:25 pm 
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The INL makes RTG's. So, are the Europeans trying to get out of paying for something?


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PostPosted: Jul 13, 2010 8:35 pm 
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Ida-Russkie wrote:
The INL makes RTG's.

....when there is Pu-238 to make them from.

There isn't anymore.

You have three guesses why (hint: the answer includes the letters 'D', 'o', and 'E')


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PostPosted: Jul 13, 2010 9:01 pm 
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Very sad....

I think the U.S. has been getting its Pu-238 from Russia for some time.

I also thought that LANL encapsulated the material. Did they fumble that football? (note: there are quite a few steps in assembling an RTG, which may be distributed across the DOE and NASA).


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PostPosted: Jul 13, 2010 11:22 pm 
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I wish they turned to easily available Sr-90. Saves unnecessary movement of highly radioactive materials.


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PostPosted: Jul 14, 2010 12:36 am 
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Hang on, I thought Sr-90 had both a shorter halflife than Pu-238 and didn't just emit alphas. How would that be "saving on unnecessary movement of highly radioactive materials" if you're shipping RTG-sized lots of Sr-90 about ?

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Self-referential - see circular logic

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PostPosted: Jul 14, 2010 6:29 am 
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Alex Goodwin wrote:
Hang on, I thought Sr-90 had both a shorter halflife than Pu-238 and didn't just emit alphas....
True, as discussed last year


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PostPosted: Jul 01, 2011 1:20 am 
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Radioisotope Power Systems: An Imperative for Maintaining U.S. Leadership in Space Exploration (2009)
Aeronautics and Space Engineering Board (ASEB)
Space Studies Board (SSB)

http://books.nap.edu/openbook.php?record_id=12653

(Thanks Jess)


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PostPosted: Jul 02, 2011 12:43 am 
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So why WAS CPP shutdown and decommissioned? $$$?


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PostPosted: Jul 02, 2011 1:28 am 
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What is cpp? Idaho chemical processing plant? Once known as CPP.


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PostPosted: Jul 03, 2011 12:01 am 
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Yes.


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PostPosted: Nov 08, 2011 5:43 am 
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Today NPR runs a story on NASA RTG shortage:
The Plutonium Problem: Who Pays For Space Fuel? by Nell Greenfieldboyce


For convenience, here are (some) other relevant threads:
viewtopic.php?f=2&t=2195
viewtopic.php?f=49&t=2049


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PostPosted: Nov 08, 2011 6:02 am 
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The Wiki entry on Radioisotope Thermoelectric Generator suggests that Am-241 is the next best thing after Pu238.

There's no shortage of Am-241 and it is commonly used in smoke detectors that you put in your house so maybe people will not feel so bad about it. One needs more Am-241 for a given heat rating, but its not too bad and the shielding requirement isn't that bad either.

The Wiki entry mentions high gamma and neutron activity from curium isotopes. I don't understand why it is that much worse, Pu238 also has spontaneous fission producing gammas and neutrons.

Strontium does have a lot of gamma activity, but probably is a great contender in deep sea remote powering where shielding weight is less of a concern (strontium fluoride also being insoluble in water is nice too).


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PostPosted: Nov 08, 2011 7:21 pm 
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The longer half-life of 241Am would be a bonus for longer duration space missions, especially if coupled with more durable Seebeck effect thermocouples.


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PostPosted: Nov 08, 2011 8:07 pm 
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90 years is already a pretty long space mission, I don't think reducing the power 4x and making it last 4x as long is a benefit.


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