In the late 1950s, the United States was losing the space race. The U.S.S.R. put the first satellite in orbit and successfully completed the first manned space flight. The U.S. needed something to prove it could compete with the Soviet superpower.
So it decided to nuke the moon.
Project A119, also titled “A Study of Lunar Research Flights,” was actually a plan to detonate a nuclear warhead on the lunar surface. The U.S. officials behind the plan hoped it would scare the Soviets and enthuse the American people.
The impressive display was chosen because the nuclear flash would have been visible to everyone who could see the moon — all things considered, not the easiest way to get a world-wide audience. It wouldn’t have been a full hydrogen bomb, however. Although the hydrogen bomb was at that point the most powerful weapon in the U.S. arsenal (and hundreds of times more explosive than standard atomic bombs), the H-bomb was thought to be too heavy to successfully launch the 384,400 km to the moon’s surface.
The plan to nuke the moon was ultimately scrapped for a number of reasons, the main ones being that the scientists were unsure what effects the bomb’s blast would have on the Earth (probably a fairly important thing to keep in mind) and that while they agreed it would have the desired effect on the Soviets (terror), it would not have the same hopeful effect on the West (the reaction would probably also be terror). Additionally, NASA didn’t want to jeopardize any future non-nuclear-explodey missions to the moon with leftover fallout.
One of the scientists on the project was a very young Carl Sagan. After the project Sagan went on to host the Emmy-winning 13-episode PBS show Cosmos, where his distinctive voice ushered a generation of young inquisitive minds through outer space. At the time it aired, Cosmos was the most watched PBS show in history. In the 1980s, Sagan wrote the science fiction novel Contact, which was later adapted into a movie starring Jodi Foster.
His sequel to Cosmos, A Pale Blue Dot, is famous for the sequence embedded below, where Sagan compares the relative magnificence and insignificance of the Earth.
Sagan’s role in the project (he was a graduate student at the time) was to figure out what would happen with dust and debris kicked up from the explosion. It’s likely that his research was at least part of the reason the plan was scrapped.
The Soviets also had a similar plan to nuke the moon, although that plan was to come after three non-nuclear missions. The Soviet plan was scrapped for similar reasons to the American one.