The reactor would launch to the moon by 2030, according to a directive by Acting NASA Administrator Sean Duffy that was sent to NASA officials in July and obtained by NPR. It's an ambitious target that has some in the scientific community concerned about high costs and a potentially unrealistic schedule.

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

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.