The Reason That NASA Has Not Returned To The Moon?
If you have 10 minutes to spare this might give you a bit of a laugh:
Link: The Real Reason Why They [NASA] Haven't Been Back To The Moon
In a nutshell: The Moon is crawling with aliens and NASA was warned not to return. Document R-2-7-7 details nearly 600 strange events occurring between 1540 and 1967 and includes contributions from some of the worlds' most famous astronomers.
See if you can sit through the entire 10 minutes 34 seconds. I did but it was hard work [gets a bit slow about 5 minutes in]
Edit: Closest match to the NASA PDF alluded to in the video:
Link: NASA Technical Report TR R-277
PDF runs to 64 pages.