why do we have days months and years

Why are there twelve months in the year? Julius Caesar's astronomers explained the need for 12 months in a year and the addition of a leap year to synchronize with the seasons. At the time, there were only ten months in the calendar while there are just over 12 lunar cycles in a year. The months of January and February were added to the calendar and the original fifth and sixth months were renamed July and August in honour of Julius Caesar and his successor Augustus. These months were both given 31 days to reflect their importance, having been named after Roman leaders.

Why seven days in a week? While months, years and days can be directly related to astrological events like the rotation of the Earth around its axis or a complete orbit of the Sun, a week is a curious 23% of a lunar month. Nevertheless, it has been used from China to India, the Middle East and Europe for centuries or more. Our use of the seven-day week, can be traced back to the astronomically gifted Babylonians and the decree of King Sargon I of Akkad around 2300 BCE. They certainly venerated the number seven and before telescopes the key celestial bodies numbered seven (the Sun, the Moon and the five planets visible to the naked eye).

The seven-day week is closely linked to Judaism (and from the Holy Book to Christianity and Islam) based on the story of Genesis with God resting on the seventh day. For the past two millennia, Western Civilisation has had a seven-day week. Who divided the day into 24 hours? The Ancient Egyptians were the first to use 24 hours to divide the day. They divided the day into 12 hours from sunrise to sunset, and the night into a further 12 hours from sunset to sunrise.

Why are minutes and hours divided into 60? When the hour was divided into 60 minutes, consisting of 60 seconds, the number 60 was probably chosen for its mathematical convenience. It is divisible by a large number of smaller numbers without a remainder: 2, 3, 4, 5, 6, 10, 12, 15, 20 and 30. Calendars from around the world, written by Alan Longstaff
The moon is where the concept of a month comes from. Many cultures used months whose lengths were 29 or 30 days (or some alternation) to chop up a year into increments.

The main problem with this sort of system is that moon cycles, at 29. 5 days, do not divide evenly into the 365. 25 days of a year. When you look at the modern calendar, the months are extremely confusing. One has 28 or 29 days, some have 30 days and the rest have 31 days. According to the World Book Encyclopedia, here is how we got such a funny calendar: This little history explains why we have 12 months, why the months have the number of days they have, why leap day falls at such an odd time and why the months have such funny names. What about weeks?

Days, months and years all have a natural basis, but weeks do not. They come straight out of the Bible: This fourth commandment, of course, echoes the creation story in Genesis. The Romans gave names to the days of the week based on the sun, the moon and the names of the five planets known to the Romans: These names actually carried through to European languages fairly closely, and in English the names of Sunday, Monday and Saturday made it straight through. The other four names in English were replaced with names from Anglo-Saxon gods. According to