New Delhi: In a warning, the US government has expressed concern over the shortage of plutonium, which can cause an obstacle in NASA’s plans for deep space missions.
The break in production of plutonium 238 (Pu-238) between 1988 and 2015 could result in a bottleneck situation, where there is not enough of this scarce resource to power spacecraft during long-duration missions, Newsweek.com reported this week citing a government report.
According to the US Government Accountability Office (GAO) report, NASA has longe since been dependable on radioisotope power systems (RPS) to generate reliable electrical power and heat energy for long-duration space missions.
However, the lack of this crtical fuel could put a dampener on NASA’s current plans for solar exploration, since its supply could be exhausted within the next decade.
RPS can operate where solar panels or batteries would be ineffective or impossible to use, such as in deep space or in shadowed craters, by converting heat from the natural radioactive decay of plutonium-238 (Pu-238) into electricity.
Missions such as Mars Curiousity rover and the Voyager 1 and 2 spacecraft use radioisotope thermoelectric generators as power source.
The production problems of Pu-238 and subsequent risks to NASA have been known for several years.
The Department of Energy (DOE) and its predecessor agencies have been providing Pu-238 and fabricating RPS for NASA and other federal agencies for more than five decades decades.
DOE currently maintains about 35 kgs of Pu-238 isotope designated for NASA missions, about half of which currently meets the power specifications for spaceflight.
Specifically, NASA plans to use about 3.5 kg of Pu-238 isotope for one RPS to power the Mars 2020 mission, the Government Accountability Office report said.
NASA may also use an additional 10.5 kg of Pu-238 isotope for its New Frontiers #4
mission if three RPS are used.
If DOE’s existing Pu-238 supply is used for these two missions, NASA would be forced to eliminate or delay future missions requiring RPS until DOE produces or acquires more Pu-238, the report said.