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The seven-day week traces back to ancient Babylonian lunar tracking
Quarterly moon phases inspired the ancient seven-day weekly calendar cycle
Unlike months or years, the seven-day week cycle has no precise astronomical length, but traces back to ancient Babylonians who observed seven prominent celestial bodies: the Sun, Moon, Mars, Mercury, Jupiter, Venus, and Saturn. They divided monthly moon phases into quarter periods of roughly seven days each.
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Tags: calendar, history, astronomy
The seven-day week traces back to ancient Babylonian lunar tracking: the short answers
- Where does this come from, and can I check it?
- Quarterly moon phases inspired the ancient seven-day weekly calendar cycle. The figure is taken from Encyclopaedia Britannica, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.
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