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View Full Version : No Go for Plutonium-238 in DOE Appropriations Bill



Ilya
2009-Oct-19, 01:23 AM
http://spacepolicyonline.com/pages/index.php?option=com_content&view=article&id=439:no-go-for-plutonium-238-in-doe-appropriations-bill&catid=67:news&Itemid=27

That's bad. Obama asked Congress for $30 million to begin the process of restarting Pu-238 production for deep space missions, and was denied.

Siguy
2009-Oct-19, 01:38 AM
That's really a shame. What does NASA have in reserves? Not much I'd bet. It seems that it was unnecessary to include an RTG on the Mars Science Laboratory, but then again, are there any other deep space probes that would require one in the near future?

Do any other countries produce Pu-238?

Ilya
2009-Oct-19, 01:51 AM
NASA has enough for Mars Science Laboratory, for next Discovery probe (not yet selected), and for Europa Flagship. And all of that was bought from Russia.

No other country makes Pu-238 because it really has no uses other than in deep space. And it is not a byproduct of weapons development, or of anything else -- the only way to get it is to make it on purpose.

Tuckerfan
2009-Oct-19, 03:18 AM
There's some talk of using positrons for energy on deep space probes. (http://www.kgw.com/news-local/stories/kgw_053009_education_wsu_anti-matter.3161fd9b.html) Not holding my breath that we'll see it any time soon.

publiusr
2009-Oct-19, 05:21 PM
We are a long way from anything like AIMSTAR. Maybe next year, Obama can try again.

tlbs101
2009-Oct-19, 07:06 PM
There's some talk of using positrons for energy on deep space probes. (http://www.kgw.com/news-local/stories/kgw_053009_education_wsu_anti-matter.3161fd9b.html) Not holding my breath that we'll see it any time soon.

I watched the video (that's my alma mater, BTW... Go Cougs!). In the background I recognized the nuclear decay chains they were using to generate positrons.

I had come up with the exact same chains back in the early 1980s and a way to capture the positrons. The thing I never did was to investigate how much energy it would take to do the capturing, nor do any kind of detailed design -- my stuff was conceptual. As for the storage method -- I was figuring on using a magnetic bottle like they had in the lab.

If, indeed, thay can use those etched compartments for containment of individual positrons and fit 10 million in a soda-size-can, the safety systems (unfortunately) might dwarf the actual containment vessel. It still may be impractical for deep space use because of that.

If anyone is interested in how it works, let me know.

I stumbled upon that nuclear chain while trying to put a little bit of science to Star Trek's, "di-lithium".

.

Glom
2009-Oct-19, 07:29 PM
NASA's stockpile is ever dwindling. It'll be at half strength within 90 years.

Tuckerfan
2009-Oct-19, 07:29 PM
If, indeed, thay can use those etched compartments for containment of individual positrons and fit 10 million in a soda-size-can, the safety systems (unfortunately) might dwarf the actual containment vessel. It still may be impractical for deep space use because of that.How big and how heavy? We've launched a number of probes that were roughly the size of a school bus.

mugaliens
2009-Oct-20, 06:05 AM
No other country makes Pu-238 because it really has no uses other than in deep space. And it is not a byproduct of weapons development, or of anything else -- the only way to get it is to make it on purpose.

"Since 1993, all of the plutonium-238 the U.S. has used in space probes has been purchased from Russia. 16.5 kilograms in total have been purchased. NASA is requesting funding to restart domestic production, but it is expected to take approximately 10 years to produce substantial amounts." - Wikipedia (http://en.wikipedia.org/wiki/Plutonium-238)

Launch window
2009-Oct-22, 01:11 AM
I think the Chinese are using plutonium-238 on some Moon rover in the next few years. If Obama left a footnote about the Chinese using it on their next mission I'm sure Congress would have been less inclined to cut funding



Moon Lander To Be Sample-Return Precursor

https://www.aviationweek.com/aw/generic/story_generic.jsp?channel=space&id=news/lander010107.xml&headline=Moon%20Lander%20To%20Be%20Sample-Return%20Precursor

For its nominal 90 days of surface operations the lander would shift from solar power to a Pu-238 Radioisotope Thermo-electric Generator (RTG) that China will either develop or buy abroad, probably from Russia.

Tuckerfan
2009-Oct-22, 01:44 AM
I think the Chinese are using plutonium-238 on some Moon rover in the next few years. If Obama left a footnote about the Chinese using it on their next mission I'm sure Congress would have been less inclined to cut funding

I doubt it. The Chinese own most of the US debt these days. . .