Some good news regarding NASA RTGs

Grey Havoc

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9 October 2009
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Via Slashdot:

After a 25-year hiatus, the Unites States has produced its first non-weapons grade plutonium needed to power space probes when solar energy won’t suffice.

NASA has been using a radioactive material called plutonium-238 to power its deep space probes since the 1970s.

The nuclear-powered spacecraft include the twin Voyager probes, now heading out of the solar system, the Mars Viking landers, the Galileo and Cassini missions at Jupiter and Saturn, respectively, and most recently the Mars Curiosity rover, which is seven months into a planned two-year mission.

The plutonium naturally radiates heat as it decays, which can be converted into electricity with a device known as a radioisotope thermoelectric generator, or RTG.

The U.S. produced its own supply of plutonium-238 until the late 1980s, when the Department of Energy’s reactors at the Savannah River Site in South Carolina, where the plutonium was generated, were shut down for safety and environmental issues. NASA then turned to Russia to purchase plutonium, but that supply line dried up in 2010.

Since then, the Department of Energy (DOE), working in collaboration with NASA, has been trying to restart domestic production of plutonium-238. Early results are promising.

After encapsulating the radioactive starter material neptunium, putting it into a reactor at Oak Ridge National Laboratory in Tennessee and radiating it for a month, the DOE did successfully generate plutonium, said Jim Green, chief of NASA’s planetary science division.

“This is a major step forward,” Green said at recent Mars exploration planning group meeting.

“We’re expecting reports from (the DOE) later this year on a complete schedule that would then put plutonium on track to be generated at about 1.5 kilograms (3.3 pounds) a year, so it’s going quite well,” Green said.

The fresh plutonium has the added benefit of reviving NASA's small and decaying supply of older plutonium still in storage.
On the one hand good job. On the other, how sad is it that we've lost so much that simply making plutonium is considered newsworthy?
sferrin said:
On the one hand good job. On the other, how sad is it that we've lost so much that simply making plutonium is considered newsworthy?

Not so good news:

NASA will now foot the entire bill for the United States' production of plutonium-238 spacecraft fuel, which recently started up again for the first time in a quarter-century.

The space agency had been splitting costs for the reboot with the U.S. Department of Energy, which actually produces plutonium-238. But NASA is the only projected user of the stuff, so the arrangement changed in the White House's federal budget request for 2014, which was unveiled earlier this month.

"Since the [Obama] Administration has a 'user pays' philosophy, we are now in a position to pay for basically the entire enterprise, including the base infrastructure at DOE," NASA chief financial officer Beth Robinson said in an April 10 press conference. "We'll be partnering with DOE in the next couple of months to figure out how to best do this, and how to streamline the program to produce plutonium-238." [Nuclear Generators Power NASA Probes (Infographic)]

Plutonium-238 is not a bombmaking material, but it is radioactive, emitting heat that can be converted to electricity using a device called a radioisotope thermoelectric generator. For decades, RTGs have powered NASA probes to destinations in deep space, where sunlight is too weak and dispersed to be of much use to a robot.

For example, the agency's twin Voyager spacecraft, which are knocking on the door of interstellar space, are both RTG-powered. So is the Mars rover Curiosity, whose observations recently helped scientists determine that the Red Planet could once have supported microbial life.

The DOE stopped producing Pu-238 in 1988, after which NASA began sourcing the fuel from Russia. But the agency received its last Russian shipment in 2010, and supplies have been dwindling ever since, worrying many scientists and space-exploration advocates.

So NASA and the DOE have been working together on a Pu-238 restart, which officials from both agencies have estimated will cost between $75 million and $90 million over five years.

This effort has made significant progress. NASA officials announced last month that researchers at the DOE's Oak Ridge National Laboratory in Tennessee had irradiated targets of neptunium-237 with neutrons, successfully generating small amounts of plutonium-238 — the nation's first in 25 years.

Scaling up from these early test activities shouldn't be too much of a chore, officials said.

"By optimizing the production process, it is estimated that 1.5 to 2 kilograms [3.3 to 4.4 pounds] per year will be produced by 2018. This amount will be enough to meet NASA's projected needs for future planetary missions. The Science budget request fully funds this requirement," NASA officials wrote in the agency's 650-page explanation of its 2014 budget request.

"For the first time, NASA’s request also includes $50 million to support the radioisotope power system development infrastructure through full-cost recovery mechanisms at the Department of Energy," they added.

We bought our plutonium from Russia with money borrowed from China. Yes we can!
circle-5 said:
We bought our plutonium from Russia with money borrowed from China. Yes we can!

This is not the Change we we're looking for.
You can't fool me with your Jedi realpolitic!

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