Time is an interesting concept, and it is very human.  There is the physical idea of time, one that scientists provide a measure, the second, and record time in established intervals.  The second is defined as the duration of exactly 9,192, 631, 770 cycles (or periods) of the microwave radiation of a specific energy transition in a cesium-133 atom. This is a precise atomic standard, and we see these seconds tick by in our analog and digital clocks.  But, for most of us (unless we are doing scientific measurements), time is a bit more ethereal, cultural, and subjective.

Take for the basic idea of what day it is?  You might get an answer related to the day of the week, such as Monday or Friday.  Or you might get our world standard, the day’s date (I am writing this on January 2, 2026).  But, you might get another answer depending upon the specific calendar you are using, common ones include the Julian, Hebrew, Islamic, and Chinese.  Some are based on solar observations, some lunar observations. Do a quick internet search, asking the question about the number of calendars in common use, and you will get around 40 different calendars, with the six to ten being considered major calendars.  Each calendar has a particular cultural or religious use.

Before getting a bit philosophical, let’s look at our common calendar, the International Calendar.  This calendar is based on the Georgian Calendar. It was not widely accepted until after 1752 when Britain and the British Colonies accepted the correction to the Julian Calendar. This calendar is named for Pope Gregory XIII, who proclaimed its use in 1582.  Astronomers still use the Julian Calendar. The Julian Calendar is based on the one adopted by Julius Caesar in approximately 46 BC with a few corrections and finalized in 8 CE.  The Georgian Calendar is a slight correction to the Julian Calendar in how it manages leap years.  The average length of the Georgian year is 365.2425 days as measured from equinox to equinox, i.e. a solar tropical year.  Using this calendar the error is only 1 day every 3300 years as compared to the Julian Calendar which accumulates an error of 1 day in every 128 years.  (The advantage of the Julian Calendar to astronomers is that all of the known astronomical observations have positive Julian dates, making the math easier.)

And, as noted before, there is still some debate as to the “proper” calendar.  Even our idea of the second and the synchronization of time is actually relatively new.  Historically for most communities, time was a local issue.  As commerce expanded, time and location became linked in what was known as the longitude problem, i.e. where was a ship located east or west of a given line.  The problem was solved by using sophisticated mechanical clocks measured against a reference. Hence, the establishment of Greenwich Mean Time or the GMT, and the basis for internal establishment of Universal Time (UTC) or Zulu Time.  The longitude problem was officially solved, as recognized by the awarding of a prize by the British Government, in 1773.  Yet, standardization of time was still at least a century away.

What finally made it an imperative to establish a standard time and time zones?  The advent of the railroads.  At noon on November 18, 1883, the U.S. and Canadian Railroads adopted what was then called the General Time Convention, which later became the known as “Railroad and Telegraph Time.”  The General Time Convention used the meridians (longitude) to establish time zones.  The Naval Observatory was responsible for providing the noon signal which allowed the railroads and telegraphs to synchronize the clocks based upon the convention established.  This occurred prior to formal establishment of GMT being the international standard at zero longitude.  The international agreement to establish UTC came in 1884. 

But, then there is our philosophical and personal perception of time.  We have all had that feeling that time is dragging, usually when we are “watching the clock” or impatiently waiting for something or someone.  Then there is the sensation that time has flown by, you are in the zone and are working on something and you look up and see that an hour or two has passed.  We also experience this when reflecting on the calendar, just how fast did 2025 fly by?  Or the past 3 years?  Each of us has our own perception, and those perceptions can be influenced by events and expectations.  This perception is the stuff of poets.

For now, let’s just marvel at the fact that we can monitor time in a precise way to help us understand our physical world, as well as monitor it in a way that allows us to engage with others.  Our calendars are precious things (on a personal and cultural level).  We use them to plan, as well as to reflect.  We use them as guides, as well as measurements of milestones.  Particular days have meaning, and some are just a box.  The key is that time is now, this present moment.  It can’t be stored or saved; it just is.