Mayan Astronomy:
Many Mesoamerican cultures showed a deep interest in astronomy. Many of them developed calendars and almanacs that would act as guides, allowing them to plan for planting and harvesting crops and even going to war. The Mayan calendar, dated back to 5th century BCE, was one of the most advanced and sophisticated astronomical calendars.
Persian Astronomy:
Post-Islam Persia showed a great interest in astronomy and produced some of the most gifted astronomers of that time. Arguably, the greatest of all was Abd al-Rahman al-Sufi, who in his 10th century CE “Book of Fixed Stars” gave the very first descriptions for the Large Magellanic Cloud and the Andromeda Galaxy.
Greek Astronomy:
In 240 BCE, Eratosthenes, a scholar, calculated the circumference of the Earth to within a 200km accuracy. He also calculated the tilt of the Earth’s axis (again, very accurately), developed the modern day longitude/latitude system, and also came up with the idea of the “leap year”. Greek astronomers, Aristotle, Plato and Ptolemy all proposed geocentric models of the Universe wherein the Earth was believed to be the center of the Universe with the Sun, the Moon and the stars revolving around it. Despite 3rd century BCE speculation from Aristarchus of Samos, this idea held prevalent from the 6th century BCE until the late 1500’s!