Understanding Time Zones

“What Time Is It...Where?”

Many of us take the privilege of knowing the correct time for granted.

table clock on desk

The numerous calculations that go into having time pinpointed to where the earth is in relation to the sun as well as seasonal changes boggles the mind so much that we just choose to appreciate the fact that when we look at our clocks or watches, it’s going to tell us what time it is.

When traveling or calling someone in a different country or on the other side of the U.S., we know that there is going to be a difference in hours.

Having time zones helps us to take that into consideration when doing business in other parts of the world, or for preparing for possible jet lag on a trip out east.

Why are time zones necessary?

If you can visualize the earth on a stick, this stick is called the axis.

The earth spins on the axis and with every 360-degree turn, a full day has passed.

Degree Turn

Astronomers refer to this 360-degree turn as a “sidereal day” which is exactly 23.9 hours.

Now imagine holding a flashlight to the earth while it is spinning on the axis.

There will be some parts of the earth exposed to the light of the flashlight and some that will be dark.

Parts of the earth will be night while the other part will be day.

If we had one standard time zone for the entire earth, it would not make sense to be noon in the part that is light and noon in the part that is dark.

Scientists took a look at the need to come up with time zones to accommodate for the differences in light and dark.

How Time Zones Were Developed

Because there are 24 hours in a day, scientists had to come up with 24 time zones. To do this they:

    • Evenly divided the earth into 24 zones, each in 15-degree-wide intervals
  • The starting point for these zones begins at the Prime Meridian in Greenwich, England. The Prime Merdian in the starting point at which all time is measured, and is point zero in relation to time zones.
  • West of the Prime Meridian is called the “Western Hemisphere”
  • East of the Prime Merdian is called the “Eastern Hemisphere”

An example of this time zone and date difference is:

New York, NY:  January 1, 2019 - 8:00 a.m.

Delhi, India: January 1, 2019 - 5:00 p.m.

There are 10 times zones between New York and Delhi, making it a 10-hour difference.

Not All Countries Follow The Time Zones

Just because there was a system of 24 time zones developed, not all countries follow their designated time zone.

This makes the whole time zone thing quite confusing and complicated, and it boggles the mind trying to understand why there isn’t a universal uniformity.

To give you a glimpse into the chaotic discombobulation, here are some countries that adopt their own time zones.


  • Recognizes 1 time zone for the entire country.
  • Uses Beijing time.


  • Uses UTC plus 4.30 hours


  • Adds 4.30 hours to time zone


  • Add 6.30 hours to time zone


  • Adds 5.30 hours to time zone


  • Add 3.30 hours to time zone


  • Has 9 different time zones
  • All zones are out of place with additional and subtracted hours


  • Has 8 time zones
    • 4 zones are nearest to the hour
    • 4 zones are nearest to the ½ hour

Sri Lanka

  • Adds 5.30 hours to time zone


  • Subtracts 3.30 hours from time zone

Time Will Tell

Most of the world follows the designated time zones, but there will always be some countries that will march to the beat of their own drum.


What’s interesting is not only are the time zones somewhat erratic for some parts of the world, the International Date Line was once a straight longitudinal line.

It was changed into a jagged line separating dates because some countries did not want to be on one side of a date but had a preference for the other side.

Trying to accommodate everyone in time zones, date adjustments, and other data that correlates to the world working together smoothly is a hopeful reality.

Until then, we do the best we can because eventually, time will tell whether or not something will prove successful.

Fun Facts About Time Zones!

  • France has the most number of time zones in the world: 12 time zones in all!
  • In 1949, China did away with five time zones going to one standard time zone which was Beijing Standard Time.
  • The North Pole and South Pole do not have time zones. There time really stands still!
  • Jet lag is worst if you travel west because our body clocks perceive the time loss and try to compensate in the form of jet lag.


Iadevai, M. (2018 February 22) 11 Things You Never Knew About Time Zones, Business Insider, Retrieved from: https://www.businessinsider.com/time-zones-facts-2017-3

(2014 April 13) Strangest Time Zones Of The World, WonderWhy, Retrieved from:


Gedge, D. (2013 July 24) Understanding Time Zones, Darron Gedge’s Geography Channel, Retrieved from: https://www.youtube.com/watch?v=X1DkiuaFCuA