History

The long human story of reading the sky — the calendars, discoveries and machines that taught us to measure the heavens.

In this reading room

• The Antikythera Mechanism — An ancient Greek geared device, recovered in 1901 from a shipwreck off the island of Antikythera, that mechanically modelled the movements of the Sun and Moon and predicted eclipses. It is the oldest known analogue astronomical computer.
• The Metonic Cycle — A period of about nineteen years after which the phases of the Moon fall on very nearly the same days of the solar year. 235 lunar months are almost exactly nineteen solar years — a near-perfect reconciliation of the Moon’s months with the Sun’s year.