Written by Myles Johnson, Sam Brass, Mason Burke, Ben Fenton and Bobby Slater
NewSpace is the latest and most innovative evolution of the space industry, which, through the reduction of legislative and financial barriers, has enabled companies and researchers to commercialise space via provision of scientific and functional capabilities.
Limitless opportunities to operate in space coupled with advancements in satellite technology have led to a rapidly expanding marketplace with an out-of-date international legislative framework. The role of nuclear material within this expansion is currently undefined, and the advancement of nuclear technologies and materials provides growing opportunities for nuclear proliferation. We must understand the factors driving companies to use nuclear material, the legislative and operational barriers to obtaining and launching nuclear material, and the danger involved when using nuclear material in space to open a discourse on nuclear proliferation within the civil space industry.
Nuclear technologies enable space exploration, providing critical heating and power to spacecrafts in otherwise inaccessible, low solar-illumination missions. They have thus seen extensive use on challenging agency-based missions in the form of Radioactive Thermoelectric Generators (RTG) and Radioactive Heating Units (RHU). In the NewSpace era, there exists a plethora of planned and envisaged space missions, many of which will capitalise on competitively priced, reliable nuclear technologies. As companies drive innovation in this area, new forms of space functionality are becoming available, including:
Although the use of nuclear material in space at present is limited, these new functionalities could provide huge sources of income in the near future, from selling nuclear technologies and materials such as NEP and americium-241 to legally mining near-Earth asteroids worth trillions of dollars. Nuclear materials are likely to succeed over other technologies because of their reliability and durability. For example, the use of an RTG on the Curiosity rover enabled almost 10x the number of scientific instruments over solar-powered options.
With such opportunities, we must wonder why private companies are yet to capitalise on the use of radioactive power sources (RPS). One barrier is the US Atomic Energy Act of 1954, which places heavy restrictions on the production, licensing, and use of nuclear material for non-research purposes by U.S. entities. As such, the National Aeronautics and Space Administration (NASA) has historically contracted the U.S. Department of Energy (DoE) to be its sole supplier of RHUs/RTGs, and since the 1980s all U.S. Pu-238 production facilities have been shut down. Additional closures of Pu-238 facilities in Russia has caused a global shortage in the fuel required for RPS.
More recently, the DoE delivered RPS for the Perseverance rover which contained Pu-238 synthesised solely by Oak Ridge National Laboratories – one of many such facilities aiming to output a combined 1.5kg per year. Despite this promising increase in supply, it is far outweighed by demand.
Private companies also face logistical challenges when using RPS. The International Atomic Energy Agency (IAEA) have published regulations for the safe transport of radioactive materials since 1961, meaning companies must submit a request to authorisation bodies, creating an extended lead-time in procurement and transport.
When it comes to launch and operation of a spacecraft containing RHU/RTG, NASA is responsible for holding a series of safety reviews with multiple federal agencies before submitting a request to the NASA Administrator or U.S. President for launch approval. Similar frameworks apply to Roscosmos (Russia). However, they are yet to be defined in Europe, so companies may have the opportunity to operate out of a country which fits their needs.
The misuse of nuclear material during a mission and lack of end-of-life planning could cause significant damage to terrestrial and non-terrestrial environments. Notably, this could result in an uncontrolled re-entry scattering nuclear material into the Earth’s atmosphere or a violation of planetary protection standards affecting other solar system bodies through the creation of spacecraft-induced ‘special regions’.
During re-entry, RTG systems can see surface temperatures of up to 3500 °C and a ground impact speed of 97 m/s. Analyses of an accidental Earth re-entry for the Cassini-Huygens Earth swing-by manoeuvre suggested that it was possible for on-board plutonium to be released into the atmosphere. The environmental impact for an accident at launch can be significant with cost of decontamination for a single mission varying between $534m and $3bn. To mitigate against the risk of release of radioactive materials, NASA and the European Space Agency (ESA) have adopted a ‘confinement and containment’ philosophy, which has so far successfully contained the plutonium dioxide fuel which landed in the Pacific Ocean during the Apollo 13 mission.
To summarise, it is possible for a company to have the intention and capability to launch nuclear material with the current lack of international cohesion between laws in the space industry. The scale of proliferation within the NewSpace era is difficult to predict. On the one hand, there is the notion that those with the most advanced, numerous and powerful nuclear-power systems are likely to win this new space-race by capitalising on the most difficult yet rewarding space missions. On the other hand, the inherent risk of damaging our planet or another celestial body may drive law-makers to establish limits on this proliferation. With this in mind, it is important to understand the driving factors, barriers and risks of using nuclear material in the private space industry and to start conversations, which ultimately may help to ensure that any form of expansion is sustainable and, most importantly, safe.
Myles Johnson, Sam Brass, Mason Burke, Ben Fenton and Bobby Slater work for Lockheed Martin, UK.