Imagine you’re driving across the Mojave Desert, and somewhere in the middle of absolutely nowhere you realize that the next gas station is further away than your car can travel on its current supply of gasoline. What next? That’s the problem NASA mission planners are facing as the agency's supply of plutonium-238, the fuel used to power deep space probes like Cassini and surface scouts like the upcoming Mars Science Laboratory, are dwindling. Unfortunately, that leaves NASA in a pretty tight spot: we’ve depleted our reserves of plutonium-238, and there isn’t anywhere to refuel ahead on the horizon either.
Plutonium-238 powers spacecraft via heat given off by its radioactive decay. A small pellet—smaller than one’s fist—glows red from its own heat and can power equipment in extremely hostile environments like the vacuum of space, where temperatures vary greatly. For missions to the outer planets or the Kuiper belt, where sunlight is a thousand times lower and the temperature near absolute zero, plutonium-238 is the only option, as solar power is too weak to provide an effective charge.
But this special brand of plutonium was a byproduct of Cold War activities and hasn’t been produced by the U.S. since the ‘80s (plutonium-239 goes in nuclear warheads, so naturally we keep plenty of that laying around). NASA has launched nearly two dozen missions over the past four decades that were powered by plutonium-238, including the Voyager probes, the Galileo probe that studied Jupiter and its moons, and the Cassini that is currently doing laps around Saturn. Those missions ran on either U.S. reserves of plutonium-238 or excess stock purchased from Russia. But now neither nation is producing the stuff, and even if we started again today, it would take eight years to build up production to the volumes necessary for annual deep space missions.
NASA included $30 million in its 2010 budget for the Department of Energy to move toward new production, but the final price tag would likely be five times that to ramp up production to sustainable levels. As it turns out, getting just the $30 million may prove impossible. The Senate chopped that number down to less-than-generous $0 during the annual budget haggle this summer; a slightly more benevolent House left NASA with $10 million for its plutonium proposal.Right now, NASA has enough plutonium-238 for the Mars Space Laboratory and the next planned mission to the outer planets. With any leftovers the agency could launch a research mission to test technology that could convert the heat from plutonium-238 to electricity more efficiently. Of course, after that there will be no more plutonium-238, so it seems that mission is a bit of a moot point. After that, NASA is grounded until it can find another fuel, or convince those holding the purse strings to turn on the cash spigot and refuel deep space exploration.
[NPR]
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To make this stuff you have to reprocess spent nuclear fuel rods, something we don't do and heavens knows why. There is allot of good stuff in them used up rods. The bad stuff has a short half life and is gone quickly leaving loads of goodies behind.
I believe the primary method of making Pu 238 is by deuteron bombardment of U238. Last I checked, there were tons of U238 available as depleted uranium for tank armour and rounds. All that's missing is a facility to generate the deuterons for the process.
right about now would be a good time for nasa to get a masive piggy bank labelled pu 238
I would think Los Alamos Labs would still have all the gear needed to do this.
I'm surprised this wasn't mentioned earlier from the Augustine Commission report.
What about weaponized U-239? Does it have the heat/decay properties needed?
In this day and age, no American Politician will consider spending money on something as "unimportant" as space exploration.
There are more "important" things to worry about down on the "surface." We have no time for proactive activities like sending humans into space beyond LEO, or exploring deep space up close with probes. Not when socialized health care for all is more important.
The more people bite into that bullshit, there won't be a toothbrush big enough to dissolve the crap that comes out of some people's mouths.
"Welcome! to the Federation Starship SS Buttcrack!!!"
There is also the fact that enriching 238 looks an aweful lot like enriching 239. Considering the non-prof gospel were shoving down NKorea and Iran, no one wants to look the hypocrite on this.
"In this day and age, no American Politician will consider spending money on something as "unimportant" as space exploration.
There are more "important" things to worry about down on the "surface." We have no time for proactive activities like sending humans into space beyond LEO, or exploring deep space up close with probes. Not when socialized health care for all is more important.
The more people bite into that bullshit, there won't be a toothbrush big enough to dissolve the crap that comes out of some people's mouths."
That's not going to stop the progress of science, and space exploration. It's still going to go on, even if it's at a slower pace; and I'm thankful for that. 3 cheers for the private sector who will do it all.
Maybe Iran will produce some we can buy...
DOE tried to address this shortage back in 2004. A draft environmental impact statement (EIS) was released in July 2005, but no final or decision has been made, yet.
See the web site - consolidationeis.doe.gov/index.html
Some points -
An earlier EIS, (DOE/EIS-0310), stated that a production rate of 5 kilograms (11 pounds) per year of plutonium-238 is expected to be sufficient to meet estimated long-term requirements and will not be revisited.
As nuclear weapons are dismantled, approximately 3,200 of these Pu-238 heat sources were originally projected to become available between 2009 and 2022.
But Los Alamos, which has supply of Pu-238 in various forms of which some is mixed with other wastes, may be part of the problem –
The Defense Nuclear Facilities Safety Board (DNFSB), in a Staff Issue Report dated April 9, 2002, stated, “The Department of Energy (DOE) has no current capability for producing Pu-238 for programmatic applications. Therefore, LANL is developing a capability to reclaim and purify scrap Pu-238. The new scrap recovery line in the Plutonium Facility (Technical Area -55) consists of six gloveboxes and will have a normal design throughput of 5 kg of Pu-238 oxide per year.”
And more importantly, in the Los Alamos National Laboratory’s Actinide Research Quarterly, 1st Quarter 2002, article, ‘To Mars and Beyond’, speaking about the scrap recovery line, it states that, “For the next two decades, it is estimated that Los Alamos will produce two to eight kilograms of plutonium-238 fuel per year to meet the needs of NASA’s space applications.” It appears that, in 2002, there was enough Pu-238 to meet NASA’s needs for 20 years.
Is DOE-Nuclear Energy throwing away very expensive Pu-238? In an April 22, 2005 LANL weekly report, the DNFSB stated that, “DOE-NE is considering if low-inventory cans can be disposed as waste instead of retained to recover the Pu-238… about half the cans in the room (~120 of 238) plus about 20 others in the vault may qualify for WIPP.”
I do not know the current status of the Pu-238 recovery line, but clearly it is not up and running. What is running is the Lab’s nuclear weapons budget, at over $1.2 billion annually.
So we have the cascade at LANL, don't we also have a smaller cascade at Oak Ridge? I know we have about a buttload of rods here in Washington, at the Hanford site, More at SATSOP. The U.S. would be doing this state a huge favor if they would come and get it. Now to the tank rounds. How much is a depleted uranium tank round worth? Our proving grounds in eastern Washington have post-impact rounds(chunks) all over the place. Is it cheaper to recycle than to spin it down? Then why is it all over the world? Is it ONLY because you don't get weapons grade material in quantity from recycling? As materials sciences expand their territories, there are new capabilities for many of the by-products of All nuclear processes. See gold-gallium-arsenide on your circuit board for reference. Big Question. Can we get a denser form of a base material like copper, or carbon even?
from Mission, B.C.
If I`m not mistaken, plenty of plutonium has been made in the past for reactors (not sure if it is the same isotope though). All that Pt is being used for is to create heat, so why not use uranium-235?
On a side note, this should be compared to our search for fossil fuel alternatives... Perhaps we should do extended and serious research into ion or plasmic drives...