Other mistake: The sphere operates through the opening and closing of Cavorite blinds to negate the force of gravity. It has no engines at all. Why then, when it lifts off from the moon, do you see a blast of what appears to be rocket exhaust?
Other mistake: Because there is no air on the moon, Cavor advises Bedford to touch helmets when they speak, otherwise they will not be able to hear each other. Yet there are several times where they seem able to communicate without doing so.