How did the people of Atlantis have accurate Earth charts detailing all the continents and star charts?

don't say "we" cause you aren't speaking for me.... and the things you claim to "know" aren't supported by any kinds of factual evidence, so I think you mean "believe". Also, atlantis never existed, and there is no connection what so ever between the Sumerians The Mayans, the Egyptians and the Greeks. You should study history instead of reading fantasy