Placing an atomic energy source on the lunar surface is “not science fiction,” experts say, but does pose technical challenges.

Nuclear reactors on the moon work in much the same way as reactors on Earth, according to Bhavya Lal, a former associate administrator for technology, policy and strategy at NASA. A controlled nuclear reaction in uranium fuel is used to generate heat that in turn can be used to make electricity.

NASA announced plans to build a nuclear reactor on the moon on Tuesday, in an attempt to stay ahead of China and Russia in a new space race. The goal is to have the reactor built before 2030, a timeline set during the Biden administration.