The world's oldest solar calendar may have been unearthed in Turkey

The markings could be evidence of two big findings: The ancient pillar could be the world's oldest lunisolar calendar, and it may serve as a memorial to a comet strike that hit Earth roughly 13,000 years ago and triggered a mini ice age.

The findings suggest that a series of V-shaped symbols on the pillars at Gobekli Tepe each represents a single day, recording the date a swarm of comet fragments hit Earth in 10,850 BC, leading to an ice age.

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