from the glowing-idea dept.
The US government says a new robot is poised to help it create a reliable, long-term supply chain of plutonium-238 (Pu-238): a radioactive material NASA requires to explore deep space.
[...] NASA tried to address the shrinking of its supply in the 1990s, but the agency and its partners didn't secure funding to create a new pipeline for Pu-238 until 2012. That work, which gets about $20 million in funding per year, is finally starting to move from the research phase toward full-scale production. By 2025, the Department of Energy hopes to meet the NASA-mandated need of 3.3 pounds (1,500 grams) per year.
Oak Ridge National Laboratory, which is located in Tennessee and leading the work, says it recently proved there is a way to produce eight times as much Pu-238 as it made just a couple of years ago, thanks to a new automated robot. [...] This week, the lab said in a press release that it's ready to push annual production to more than 14 ounces (400 grams) per year, an eight-fold increase.
Cassini carried 33 kilograms of plutonium. New Horizons had 9,750 grams (lower than the 10,900 grams, 1/3 of the Cassini amount, called for in the original design).
It's time to send a probe to Uranus and Neptune already.
The US Department of Energy announced that 50 grams of Plutonium-238 had been made by researchers at the Oak Ridge National Laboratory in Oak Ridge, Tenn. This is the first time the substance has been made in the country since the Savannah River Plant in South Carolina stopped making it in the late 1980s.
"Right now, NASA only has access to 35 kilograms, about 77 pounds, of Pu-238 to power space exploration missions. That's just enough to last into the middle 2020s, powering just two or three proposed missions."
"Two years ago, NASA began funding efforts to make Pu-238 again in ernest. The agency has put about $15 million each year toward the DOE's Office of Nuclear Energy's efforts." The next step is to automate and scale up the process.
I didn't know we had lost the capability to produce it and am glad we are starting up again. So how much Pu-238 could we make for the cost of one F-35?
A Government Accountability Office report has found that the U.S. is unlikely to produce enough Plutonium-238 for NASA missions about a decade from now. The isotope has been used in radioisotope thermoelectric generators (RTGs) on missions such as Voyager, Cassini, and the Mars Science Laboratory:
Another GAO report notes: "[...], DOE currently maintains about 35 kilograms (kg) [77 pounds] of Pu-238 isotope designated for NASA missions, about half of which meets power specifications for spaceflight. However, given NASA's current plans for solar system exploration, this supply could be exhausted within the next decade."
[...] To address the plutonium problem, in 2011 NASA provided funding to the Department of Energy (DOE) to restart domestic production of the substance. The program is called the Pu-238 Supply Project. So far, the Project has produced ∼3.5 ounces (100 grams) of Pu-238. DOE identified an interim goal of producing 10 to 17.5 ounces (300 to 500 grams) of new Pu-238 per year by 2019. The goal is to produce 1.5 kilograms of new Pu-238 per year—considered full production—by 2023, at the earliest.
GAO is questioning the Supply Project's ability to meet its goal of producing 1.5 kilograms of new Pu-238 per year by 2026. For one thing, the oversight agency's interviews with DOE officials revealed that the agency hasn't perfected the chemical processing required to extract new Pu-238 from irradiated targets to meet production goals.
Only one DOE reactor is currently qualified to make Pu-238:
NASA's plutonium will be produced at two of these reactors, but only one of them is currently qualified to make Pu-238. GAO reported that initial samples of the new Pu-238 did not meet spaceflight specifications because of impurities. However, according to DOE, the samples can be blended and used with existing Pu-238.