it comes out of the ceramic and leaves the ceramic untouched.

My epxeriments with older (not microwave-safe) ceramics suggested that the ceremic is not necessarily untouched. Sometimes the water wants to leave in a big hurry and breaks the ceramic.

Of course the moon hoaxers don't understand how microwave ovens work. It's as much a mystery to them as Van Allen belts or rocket propulsion. So it's perfectly reasonable to them that a microwave oven will "magically" alter the crystalline or chemical composition of minerals to fool expert geologists who spend their whole lives looking at such things.