Calendar, Numbers in The
Calendars have always been based on the Sun, Earth, and Moon. Ancient people observed that the position of the Sun in the sky changed with the seasons. They also noticed that ...
Development of Calendars
Keeping track of the passage of time has been a human preoccupation since the dawn of history. Calendars helped societies to understand and track the changing seasons...
The Calendar Takes Shape in Mesopotamia
The calendar used today in the West has its roots in the system developed by the astronomers of Mesopotamia—and particularly the Mesopotamian ci...
A calendar is a system of measuring the passage of time. Early peoples used the lunar month--the interval between a complete sequence of phases of the moon--to calculate time. Because a lunar...
There are three units of time which have a direct basis in astronomy: the day, which is the period of time it takes for the Earth to make one rotation around its axis; the month, which is th...