One more step has just been taken by NASA, confirming the decision of the American space agency to to turn to nuclear power for its long-term missions to the Moon. Three preliminary nuclear fission reactor designs have just been chosen for be tested on the lunar surface by 2030. Each reactor will have to produce a power of 40 kW and the agency granted in total a sum of 14.18 million euros.
A reliable source of energy is crucial to being able to establish a permanent human presence on the Moon, and later Mars. During the Apollo missions, stays on the Moon were short enough that spacecraft could use batteries and fuel cells. Today, solar energy is mostly used for space missions, but even this type of energy will not be enough to power long-duration missions to the Moon or Mars.
The harsh conditions of the Moon
Build a permanent base on the Moon is not easy. There are the cost of transporting the material which is estimated at more than 190,000 euros per kilogram. In addition, the base will be exposed to temperatures up to 120°C for 14 daysand -130°C during the lunar night which also lasts another 14 days.
Already, the fact that there is no sun for two weeks prevents the use of solar energy. The base and the equipment must indeed be constantly heated during the lunar night. All these conditions suggest that the most practical power source for the Moon is a compact source with a light weight, and which uses a fuel having a very high energy density.
What NASA is looking for
The use of nuclear energy in space is not something new. But as far as the Artemis program is concerned, a system much more advanced is necessary. This system must be modular, scalable, and must be able to operate for a period of up to ten years. The best would also be a system running on nuclear fuels other than plutonium, which is very difficult to produce.
Three companies have thus received funding from NASA in consultation with the Idaho National Laboratory of the US Department of Energy. Project contracts Fission Surface Power have been awarded to Lockheed Martin, Westinghouse and IX. These companies will develop the initial design of their fission reactor, for a period of 12 months.
The objective of the first phase is to obtain information on a demonstrator which will serve as a basis for the production of reactors for the Moon and Mars. The technology will also be used to advance the development of nuclear-powered rockets for use in cis-lunar and deep space.