Our entire everyday life is based on the decimal system, only the time is not. In a sense, hours, minutes, and seconds are a very arbitrary division in itself. The calculation of time certainly has to do with the rotation of the earth. But why is an hour 60 minutes long and not a hundred? Let’s find out.
The Reason For 60 Seconds in a Minute
When people started seafaring, they needed a more precise schedule. Columbus needed to know exactly where he was on his voyage. A deviation of two seconds would have put him one kilometer off his path. So the minute was further broken down into parts.
The reason that it is 60 seconds is due to the then common computing system, which was based on the number 60. It’s called the sexagesimal system. With the invention of the second, a much more accurate time measurement was possible.
So that our modern clocks can display the seconds, so-called unrest in the clockwork is always necessary. With large clocks, this is a pendulum, in wristwatches, a quartz stone often causes vibrations, or a spiral spring specifies the second cycle.
The atomic clock displays the most accurate time. There, the vibration of cesium atoms ensures that seconds and milliseconds can be clearly specified.
Why Is An Hour 60 Minutes Long?
The division of one hour into 60 minutes goes back to the Babylonians. The Babylonian number system was based on the number 12, which had a religious meaning, and the number 60 is a multiple of 12. The first written reference to a division of the minute into 60 seconds can only be found centuries later in late Roman times.
One of their astronomical references was the 360 sun peaks (days) a year. In analogy to this, a full circle, the revolving hands of a clock, has 360 degrees. Since the earth rotates on its axis, taking 24 hours, one hour corresponds to 360: 24 = 15 degrees. That means that every 15 degrees, there should be a number on the watch.
But since we divide clock faces into twelve hours, there is a digit every 30 degrees. That goes well with the hour of 60 minutes: 90 degrees corresponds to 15 minutes, 180 degrees to 30 minutes – and 360 degrees to 60 minutes. And that is why an hour is 60 minutes long.
However, neither minute nor second had any meaning in everyday life at that time. Rather, up until modern times, they were primarily mathematical variables and, above all, important for astronomers.
They only became important for timekeeping after the invention of the pendulum in the second half of the 17th century, when it was possible to manufacture correspondingly accurate clocks.
For the Babylonian period, it is also proven that the year was divided into twelve months based on the twelve lunations that complete the sequence of all moon phases. The day and night were divided into twelve hours each.
Another question in this context is the seven days of the week, and here too, we find several explanations or assumptions. One of them relates to the individual phases of the moon, between which there are seven days.
Another explanation refers to the seven near-earth celestial bodies Sun, Moon, Mars, Mercury, Jupiter, Venus, and Saturn, which were visible during the Babylonian period, and each of which was the godfather of a weekday.
The Roman Time calculation
The earth’s orbit around the sun takes 364 days, 5 hours 48 minutes, and 46 seconds exactly. Half a day is difficult to count, and the founders of our calendar had to round off. The importance of the number 12, which also happens to be the number of months, is related to the phases of the moon.
The number of days was also rounded off to 30/31 days in a month. February came about with lesser days because this system of timekeeping doesn’t work, or maybe it was just a way of proving that February was the least favorite among the other 12 months.
An adjustment took place in the months of Julius and Augustus because one emperor wanted to have no fewer days than the other.