Oak Ridge National Laboratory has solved the main problem of space device developers: plutonium-238 deficiency
In 2015, an article was published on Habré that a small amount of plutonium-238 produced threatened NASA’s plans to launch spacecraft on thermoelectric generators. Plutonium-238 (Pu-238) is an almost ideal fuel for satellites, rovers, and other types of space wanderers created by human hands. So, only four kilograms of fuel is enough to provide the ship with energy.
In the entire history of space exploration, NASA has spent 140 kg of plutonium, including experiments under the Apollo program, the Galileo mission, and others. But the production of plutonium-238 isotope was stopped in the USA in 1988. They bought fuel from Russia, but it was still not enough. Now the problem of deficiency seems to have been resolved..
This was done by experts at the Oak Ridge Laboratory. This week, it was reported that the bottleneck of US space programs seemed to have expanded.
NASA needs 1.5 kg of plutonium per year to fulfill its plans; the agency voiced such needs until 2025. The Oak Ridge National Laboratory managed to set up production, now the volumes have been increased from 50 grams per year to 400. Previously, all this work was done manually, but now pellets with fuel are formed automatically. Pellets include neptunium oxide and aluminum. After the pellet is formed, it is placed in the reactor, with the conversion of the contents into plutonium-238.
It is worth noting that the United States would not have problems with plutonium if it had not interrupted shipments from Russia in 2009. The problem arose due to the restructuring of the Russian nuclear industry. As a result, in 2015, NASA’s reserves were only 35 kilograms of plutonium.
In 2012, NASA was able to reach an agreement with officials on the resumption of plutonium-238 production, due to which the shortage problem was gradually solved. In 2013, the Oak Ridge National Laboratory began producing plutonium-238, but it was too little. The development was small due to the shortcomings of the technical process, most of the manipulations had to be done manually.
NASA had to tackle the problem on its own, since Congress and the White House disclaimed all sorts of obligations on this matter, and gave the agency complete autonomy in this matter. Well, since the organization had to build a plutonium production line from scratch and resume the work of the relevant laboratories, a significant part of the agency’s funding began to go for these purposes. Some scientific and technical programs even had to be stopped, including the development of new generators, which used plutonium fuel more economically.
As a solution to the problem, it was even proposed to launch vehicles operating exclusively on solar energy. In some cases, this is even a better option, since photovoltaic cells weigh less, they can be deployed, adjusting the power generation of electricity. For example, to launch a mission to Europe, you would need panels of 50 m 2 . NASA began to work on optimizing photovoltaic cells in order to produce more efficient solar panels.
But still this is only a partial solution to the problem, since some missions cannot be accomplished only with the help of solar energy. A number of devices are too far from the Sun, so that solar panels are not able to produce as much electricity as is necessary for the operation of the device. In addition, sometimes the device is simply hidden from the sun. In the case of an apparatus that landed on the Churyumov-Gerasimenko comet, an element on plutonium would be a preferable option, since in this case the device would still work, studying the comet and its surroundings.
Thus, the successes of the Oak Ridge National Laboratory will allow the US space program to develop more actively than before. Now all the devices being developed by NASA, for which thermoelectric elements are needed, will receive them on time and in the right amount.