Accounting for Time
Time is what makes our universe interesting. Without time there would be no motion, and we all know how boring it is sitting around doing nothing. Scientists and physicists are still grappling with the precise nature of time, but we may think of it as the means by which motion occurs within the realm of the other three (spacial) dimensions of our universe. We know that time and space are related because Einstein hypothesized and physicists later substantiated that the faster one travels the more time warps or slows down (relative to other objects) for that object.
As murky as the concept of time can be, we can measure it fairly accurately, and we have been doing so for centuries. It all began when the ancients devised a system whereby the days were counted by tracking the cycle of the seasons and the relative declination of the sun. They soon figured out that there were just so many days in a year (365 1/4 give or take a few minutes here and there). Then, for convenience, they divided the days into months, by using the seemingly obvious measure of the lunar cycles (which ultimately proved to be inconvenient as there are slightly more than twelve in a year). However, this got the ancient Babylonians and Egyptians thinking about the number twelve.
The number twelve became associated with time. It was decided in that murky past that both the day and the night should be divided into hours, twelve hours for the day, and twelve at night. They were measured by various means, and soon regulated to a precise length of time by use of a moving device called a clock. Dividing up hours from the day made someone decide that the hour could then be subdivided as well. The Sumerians liked the number 60 so this was used for the subdivision. This is how we came to have sixty minutes and these minutes are divided into 60 convenient seconds. As the need arose, we came to have time in even smaller parts such nano-seconds.
The motion of our planet, coupled with the repetition of the seasons made for holidays such as Easter (which has a curious way of being calculated) as well as the days of the week. But a problem occurred with early calendars. They were not entirely accurate. Since there was about an extra quarter-day every year, calendars could not be compared with those of previous years.
We are quite fastidious about measuring time because it is a useful tool for many things, including gps navigation, running a computer and any number of other gadgets. In ancient times they used calendars for determining when to plant crops, and to calculate when to schedule holidays. It was important to align the calendar year with the solar year (or the precise amount of time it took for the Earth to orbit the sun). To compensate for this, the leap year was invented. This is where 1/4 day is added every fourth year to the end of February.
Another timely innovation came as a war-time measure. In 1916 Germany and Austria switched over to Daylight Saving Time in order to save resources for fighting the French, English, and the Russians.
Thus, we can thank our forebears for our interesting manner of accounting for time, in years (some of them of the leap variety), months, days, hours, minutes, seconds, and nano-seconds.
As much as we know about time, there are still many things we do not completely understand, its precise relation to speed and gravity, or whether it can move backward as well as forward. We do know that time is a valuable commodity. It is incumbent upon us to use it wisely.
Codes and Signals