A page from the "Calendars" exhibit...

Announcing the Sky


L'atmosphère: météorologie populaire

by Camille Flammarion (1888)

The schedule of our lives is shaped by the movements of the earth, moon, and sun.

In ancient Rome, a priest observed the sky and announced a new moon cycle to the king. For centuries afterward, Romans referred to the first day of each new month as Kalends (from their word calare, which means "to proclaim”).

The word calendar derived from this custom.

Learn about astronomical origins Explore various calendars