The Sumerians knew about Uranus, Neptune and Pluto. They knew about the large planet, in the non-standard, massive orbit (3600 years) that NASA is now looking for. They knew about the cycle of the precession of Our Earth, which is about 26,000 years. They knew the value of Pi.
They knew about almost every basic science and tech that is the core of our civilization today. Some of their residents left for Greece, to help start it's ascent, along with people from Crete, and other Mediterranean isles.
The Sumerian civilization was the core of our current civilization, and the core foundation for Egypt, India and China. You can also read about the amazing knowledge of a large number of amazingly long astronomical cycles that the Mayans knew about.