2. A foundation built on clay

Present day historians echo Ptolemyís claim. They profess to have uncovered old cuneiform tablets with observations dating back to exactly 747 BC.

Apparently some of the Babylonian records available to Ptolemy made their way into the archives of present-day museums. Historians and astronomers collaborated to date the records and fine-tune chronology. The resulting time-line is considered astronomically sound from the present to the 8th century BC.