Amidst the scientific progress, big egos, and general madness of the Cold War, the US wanted to drop a nuclear bomb on the Moon. The idea was sold as being in the interest of science, but really it was just a big middle finger to the USSR. As if this cautionary tale couldn't get any weirder, a young Carl Sagan was one of the bright sparks used to hatch the plan.
A declassified report by the Air Force Nuclear Weapons Center from June 1959 shows just how seriously they considered the plan, called Project A119. In general, they wanted to investigate the capability of weapons in space, as well gain further insight into the space environment and the detention of nuclear devices.
The report explains: ”The motivation for such a detonation is clearly threefold: scientific, military, and political.” Within the 190 pages, they discuss at length the possible effects on the lunar surface, how they could conduct seismic observations on the Moon during the blast, and how long the radioactive fallout might last.
Their idea was to drop a small W25 nuclear warhead along with the Moon’s terminator (the division between the illuminated and shadowed parts). This means the mushroom cloud would be lit up by the Sun and could be seen from Earth and, in particular, viewable from Moscow. All of their research showed they did indeed have the technological clout to pull this off.
The bomb would have boasted a 1.7-kiloton yield. That's relatively low for an A-bomb, but it's still no joke. For context, you can watch the video below that shows the Soviet’s RDS-37 1.6-kiloton yield bomb. As you can see, it's still utterly terrifying.
The grand plan of Project A119 was led by Dr Leonard Reiffel (who later became the deputy director of NASA’s Apollo program), high-ranking officials in the US Air Force, and a few of the West’s top scientists, including Gerard Kuiper, a major figure in modern planetary science.
Carl Sagan, the legendary science prophet, also worked on the project. Years before he became an outspoken critic of nuclear weapons, he was employed by Reiffel to work out how big and visible an exploding dust cloud in the space around the moon would be. Sagan's name even appears on the report’s list of contributors at the top of the declassified report.