Carl Sagan saves the moon from a nuclear attack.

In 1957, the United States was very nervous; its enemies in turn, the Soviets, had proven to be ahead of them in the space race by putting Sputnik 1 into orbit, the first artificial satellite launched on October 4, 1957, just in time to celebrate the 40th anniversary of the October revolution. To give you a little context, winning the space race was important because it demonstrated which power was capable of destroying the other in a nuclear missile war, and putting Sputnik 1 into orbit made it clear that at that time the Soviet Union was superior. In this climate of uncertainty a little less than a month later, on November 1st, a note appeared in the United States newspapers. The note said that an anonymous source informed the news agency that someone high-ranking in the United States intelligence services had told that anonymous source that they knew that on November 7, the very day of the anniversary of the Soviet Revolution, the Russians would detonate a hydrogen bomb on the Moon to demonstrate their technological and military superiority. November 7 would coincide with a lunar eclipse, which would make the flash of the explosion more visible because the Moon would be in the shadow of the Earth and would not be as bright, but the source supposedly leaked the information also said it could be a few days before or a few days after the eclipse. By detonating the bomb another night when there was no full moon, they could take advantage of the dark side of the terminator line, the terminator is the division of the illuminated part and the part that is not illuminated by sunlight of any body, other planets, the Earth or the Moon, could be asteroids and it is the word that James Cameron used to call his time-traveling killer robot because it sounds like Terminator in English.

Fortunately, November 7th came and went and no Soviet rocket bombed the Moon, but the United States with its chronic paranoia said "Nothing happened so we have to try to do it ourselves first." What do a lot of military people do when they have a plan that they have no idea how to carry out? They go to universities to recruit brainiacs. That worked very well for them in the Manhattan Project with which the United States built, tested and used the first three atomic bombs. The United States Air Force commissioned physicist and professor at the University of Chicago Leonard Reiffel to form a team of scientists with the purpose of studying the scientific value that detonating hydrogen bombs could have, near and on the Moon. The most advanced project is called Project_A119.

This can be translated as "we want to bomb the Moon to show off to the world our military capabilities, but we need you brainiacs to give us a scientific excuse to do it that sounds valid", they themselves knew that bombing the Moon would definitely make them less popular with the rest of the world and it is known that they love to be disliked, but altering the moon, something that absolutely all human cultures adore, some literally, perhaps was going too far, for this reason the military wanted to find a credible scientific argument that would be the excuse for their absurdity.

Leonard Reiffel accepted the job, although he probably had no other option and put together a team of 11 scientists to help him, among them the young Carl Sagan. Sagan was responsible for doing the mathematical calculations to predict the expansion of the dust cloud produced by the explosion and determine how visible it would be from Earth. At first, a hydrogen bomb had been considered, which is much more powerful and destructive than an atomic bomb. The most powerful hydrogen bomb was the Soviet Tsar bomb, which was more than 3,000 times more powerful. than the bomb that the United States detonated over Hiroshima at the end of World War II. The more powerful the explosion on the Moon, the more visible it would be from Earth, but using a hydrogen bomb was ruled out because they were still too large and heavy for their existing rockets to carry to the Moon. Instead, a 1.7 kilo W25 warhead would be used that barely had a tenth of the power of the Hiroshima bomb, but was small and light enough to be carried by an existing missile conditioned for the long trip to the Moon. The atomic bomb would be small, so They would try to detonate it where the explosion was most visible, the main target being a dark region near the terminator.

There, not only would the flash of the explosion be visible, but the cloud of dust raised by it would rise to altitudes where it would be illuminated by sunlight. contrasting with the dark background making the explosion and its effects even more spectacular, at least that was the plan and Carl Sagan had to prove it with mathematics, this would not be easy because in reality at that time we knew practically nothing about the Moon, we could see the surface with telescopes from the Earth, but we did not know its properties to predict what would happen. At that time, we had not even ruled out that life forms existed there and this was especially a problem for the young Carl Sagan who since then was interested in astrobiology, a discipline that studies the conditions that foster life and its evolution to try to discover its traces beyond Earth, but from a scientific point of view. The scientific community still did not know if there was any form of life on the Moon and the United States planned to bomb it with nuclear weapons. Sagan's conclusion in his report discouraged the military because he mentioned that a detonation as small as the one they were capable of carrying out, although it could be visible with powerful telescopes under certain circumstances, was definitely very far from being able to be seen with the naked eye, which was exactly what the Air Force was looking for. It would be necessary to check his calculations to see if Sagan did not intentionally manipulate his results to discourage the military, who already saw themselves leaving their mark on the Moon, even so, a decade later they would achieve it in a much more subtle and less destructive way.

Another part of the study focused on knowing the scientific value of placing seismographs on the Moon to record a nuclear detonation and in this part the scientists reported, without fear, that if purely scientific knowledge was sought, placing seismographs on the Moon would fulfill that purpose without having to use explosions since the constant meteorite impacts would be enough to obtain valuable data on the internal composition of the Moon. The conclusion of the study was that bombing the Moon would not help study it much more than sending measuring instruments and that doing so would entail a very great moral cost since public opinion would not view these explosions favorably.

Whether Sagan manipulated his results or not, that was not the only subtle sabotage of the United States' plans to bomb the Moon, this research was classified, a leak of this information was a violation of national security, even so, Sagan mentioned the secret reports in his application for a scholarship at the University of Berkeley in California, making it public and when the existence of this project became known, people's reaction was obviously negative.

Thanks to this, it was possible that in the 2000s the original document was declassified to make it public, unfortunately when you get to chapter 9 it tells you that it is in volume 2 of the report and that volume along with other documents related to this secret project were destroyed in the 80s by the Chicago Institute of Technology, this makes you think that there was something more in that report that the United States government wanted to hide permanently, something worse than the plan to bomb the Moon, but they never did. we will know.