One Sky Many Calendars: 25 Ideas That Explain How We Measure Time

Time feels simple until you start asking questions. Why does a year have 365 days? Why does the Moon change shape every night? And why do some festivals move across the calendar while others stay fixed? Across the world, people have looked at the same sky and created very different ways to measure time, each one shaped by observation, culture and need.

This book takes young readers on a fascinating journey through time, sky and human ingenuity to uncover the hidden logic behind calendars.

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