Ganymede: Ganymede is both the largest moon of Jupiter, our Solar System's planetary behemoth, as well as the largest moon in our entire Solar system. Observations of Ganymede by the HST in 2015 suggested the existence of a subsurface saline ocean. This is because patterns in auroral belts and rocking of the magnetic field hinted at the presence of an ocean. It is estimated to be approximately 100 kilometers deep with a surface situated below a crust of 150 kilometers.
The conspiracy that Fox missed (well, they do miss a lot) is called by its adherents "Alternative 3". Its promoters are shadowy individuals like Bill Cooper, a formal US Naval Briefing Team member with access to state secrets, who claims that an advanced American space presence is a reality. In Behold a Pale Horse, he reports that "A moon base, Luna, was photographed by the Lunar Orbiter and filmed by Apollo astronauts... I can say that 'Alternative 003' (a British TV documentary on this subject) is at least 70% true from my own knowledge and the knowledge of my sources."
A billion years ago, our Moon was closer to Earth than it is now. As a result, it appeared to be a much larger object in the sky. During that ancient era, if human beings had been around to witness such a sight, it would have been possible to see the entire Moon--not merely the one near side face that we see now. A billion years ago, it took our Moon only twenty days to orbit our planet, and Earth's own day was considerably shorter--only eighteen hours long. Stupendous, almost unimaginably enormous tides, that were more than a kilometer in height, would ebb and flow every few hours. However, things changed, as the lunar orbit around our primordial planet grew ever wider and wider. Annually, Earth's Moon moves about 1.6 inches farther out into space. Currently, the lunar rate of rotation, as well as the time it takes to circle our planet, are the same.