How did people imagine the solar system in ancient times?

Ancient Egyptians and Greeks.
The peoples, whose level of development was higher, got the opportunity to travel to distant countries and saw that in the world there are not only mountains, or steppes, or forests. They envisioned the Earth as a flat disc or a high mountain surrounded on all sides by an endless sea. The vault of heaven in the form of a huge overturned bowl sank into this sea, closing the small universe of the ancient world, such ideas existed among the ancient Egyptians and Greeks. According to their cosmogonic version, the Sun deity rolled along the firmament in a fiery chariot every day, illuminating the plane of the Earth.