This was uncovered to be just a hair fiber that got scanned on the film. The images were widely distributed in this form. The original photos do not have this C.
A magnification of this "C" shows a secondary mark that appears to be a shadow is clearly visible under the top portion of the mark, which supports the fact that the "C" was a hair fiber on film.
Note the secondary mark - a shadow.
Comments
“If people decide they’re going to deny the facts of history and the facts of science and technology, there’s not much you can do with them. For most of them, I just feel sorry that we failed in their education.”
– Harrison “Jack” Schmitt, Apollo 17 astronaut
How does stage magic work, again? Simple, by tricking the brain. In order to survive on this planet, we are compelled to understand and calculate our movements and almost everything based on the environment we are given: we aren't neurologically wired to think outside that. To think that maybe the laws we learned in infancy are not applicable.
Our senses and what may seem like perception are very linked: if we never question them, we won't get very far.
Conspiracy theories have many positive traits that are laudable, on one hand. They question things: establishments, the way things are run, how actions were truly carried out, etc.
They are also the bearers of incredible flaws: they totally miss the point. The approach is ridiculous, they question things but in the totally wrong way.
The most important thing is habit, and your approach to anything must be built through habit. In order to understand if an approach is beneficial it needs to be broken down, analyzed and then analyzed in comparison to other approaches and their products. The approach is everything, especially in the most elementary of tasks, such as thought and deduction.