8 What Time Is It?

As one of the oldest sciences, if not the oldest, astronomy was important in people’s day-to-day lives. The calendar was important due to agriculture and the influence of seasons and time. The oldest calendar dates back to 4800 BC and was found along the Egyptian-Sudanese border. Some of the African calendars even marked predictions of lunar phases.

Astronomy and time had a major link for early civilization. Before the clock, people depended on the positions of the Sun, Moon, and stars to tell the time, both daily and the time of year. During the day, people observed the Sun’s path, looking at shadows – pre-sundials. During the night, the Moon’s position and phase and star positions were observed. And throughout the year, people looked at the Sun’s seasonal position.

The days of the week that we still use are named after astronomical objects.


  • Sun
  • Moon
  • Mars
  • Mercury
  • Jupiter
  • Venus
  • Saturn

TEUTONIC NAME (Germanic Tribe)

  • Sun
  • Moon
  • Tiw
  • Woden
  • Thor
  • Fira
  • Saturn


  • Sunday
  • Monday
  • Tuesday
  • Wednesday
  • Thursday
  • Friday
  • Saturday

Why is there a 24-hour Day? Why not break the day into 10 segments? Or 1,000,000? We can attribute it to the Sumerians, over 4000 years ago. First, they used their fingers with three divisions each to count and their thumb as a counter. The Sumerians divided the day into 12 units (2 hands) and night into 12 units. The Ancient Babylonians inherited the Sumerian 24 hour day and presumably added their ‘base 60’ counting system; one hour into 60 minutes, one minute into 60 seconds.

There were – and still are – calendars based on the Moon . These Lunar calendars have periods of 29 or 30 days. Think of our common word month: from Moonth .

Some examples of Moon-based Calendars include the Metonic and Jewish calendars. The Jewish Passover, thus New Testament Easter is also based on this calendar. Other calendars include the Saros, based on eclipse cycles of 18 years, and the Mayan calendar, 260 days based on eclipse seasons.


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