| Date | Development | |
| 9000 BC to 8000 BC | A marked bone (possibly) indicating months and lunar phases in use in Ishango (Zaire) | |
| 4228 BC to 2773 BC | The Egyptians institute a 365-day calendar. The start of the year, coinciding with the annual Nile floods, is linked to the rising of Sirius (the Dog Star) in line with the Sun. | |
| 1500 BC to 1450 BC | L-shaped sundials used in Egypt | |
| 1450 BC to 1400 BC | Stonehenge achieves the form known today | |
| 1292 BC | Pharaoh Seti I dies in Egypt. His cenotaph contains instructions for constructing and using a sundial. | |
| 730 BC | The "miracle of Ahaz" is performed in Judaea by the prophet Isaiah. (see under Ahaz, dial types) | |
| 600 BC to 590 BC | Sundials are used in China and the Chinese text "Arithmetic classic of the gnomon and the circular paths of the heaven" contains a version of the Pythagorean theorem. | |
| 586 BC | Pharaoh Psammeticus erects an obelisk in Heliopolis (Egypt) | |
| 585 BC | Thales of Miletus (now in Turkey) is said to have correctly predicted a solar eclipse. | |
| 520 BC to 510 BC | Anaximander introduces the sundial (previously used in Mesopotamia, Egypt and China) to Greece. He also produces a cylindrical model of the Earth. | |
| 500 BC to 490 BC | The Pythagoreans (Greece) introduce a spherical model of the Earth. | |
| 480 BC to 470 BC | Greek philosopher Oenopides calculates that the axis of the Earth is tipped over by 24° from the plane of its orbit. | |
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