Today almost everyone who is old enough to crawl has a smart phone with him or her. Watches are passé and lesser and lesser people are sporting one. The ones who are do that for fashion purposes and not so much to tell time. When someone asks you “Is it noon yet?” or “What time is it?” all you got to do is flick a button and bingo you know the time.
But is telling time as simple as that?
Yes, we have made it simple and it is quite easy as long as we stay in the same country … and in the same time zone. Let us look at India. When someone asks you “Is it noon yet?” s/he is asking if the time is 12 noon. Let us assume it is exactly 12 noon when the question was asked. Let us also assume that this conversation is taking place between two people relaxing at the Dwarka beach in Gujarat, one of India’s westernmost locations. Switch to two other individuals having the same conversation at the very same time … but this time sitting on a meadow in Tezu in Arunachal Pradesh, part of the India’s easternmost territories. Both answers by both people will be affirmative, “Yes, it is noon.”
Now comes the tricky part. Let us take five more such couples ad they are having this conversation sitting in Islamabad, Kathmandu, Colombo, Thimpu and Dhaka. At that exact same time the answers will be very different. In Islamabad the time is 11:30am, 15 minutes past noon in Kathmandu and half past noon in Thimpu and Dhaka. Only the couple in Colombo will agree with the two couples in India.
Therefore, within the noon time that exists between the two ends of India, there are other places with completely different times.
It is convenient to divide countries into specific time zones so that there is no chaos, at least within the country. If the country is larger … let’s say United States or Canada, the country itself is divided into multiple time zones.
So, to repeat the question, “Is it noon yet?” the answer is not as simple as looking at a watch. We need to look at the Sun instead. Once we use the Sun to find our answer, all other towns and cities and countries will fall into a comparative time zone … Zulu Time many people call it.
Time as we know it is relative to the time in the little village in that little island in whose empire the Sun never set – England. Greenwich to be more specific. Time zones all around the world are relative to the time at Greenwich.
Now let us try and answer the question, “Is it noon yet?” Celestially speaking, noon is that exact instant in the time continuum when the Sun is at its highest point in the sky. Simple. And this is regardless of whether you watch says it is 12 noon or not. In fact, at most times, if not all the time, our watches are incorrect. Noon is not always at 12 o’clock in the afternoon. To know when noon occurs you need to know when the Sun is at its peak. How do you do that? Simple. All you need is a clear day, a Sun that is shining bright, and a stick a couple of feet long.
Go out to a location that is flat and not obstructed by shadows of trees, buildings or other structures. Plant the stick vertically on the ground, keeping it pointed straight up in the sky. You will notice that the since light cannot pass through solid objects (and I am disregarding Einstein and his theories of bending light and so forth) the stick casts a shadow on the ground, opposite to where the Sun is located. Make a mark at the end of this shadow. Take another marking every ten minutes or so. As you keep taking these markings, you will notice the shadow first becoming shorter and then becoming longer. Keep note of the exact point where the shadow is the shortest. By the way, the shadow distance is measured from the base of the stick to the end of the shadow.
The shadow formed by the stick is the shortest when the Sun is at its zenith. Bingo, you have found the time when noon happened.
And that is 12 noon at your location according to the Sun. But what time is it really? Reference to Greenwich Mean Time? Unfortunately you will have to depend on your good old watch for that answer … the Sun does not help here. Your watch needs to be calibrated to Greenwich Mean Time
At the location I am penning this, the longitude is 77.2 degrees East of Greenwich. That means when noon happens at my location it is 0651GMT. And that is what your watch will show. If you believe in the Indian Standard Time, then the time will show 0630 GMT, which is obviously incorrect at my location, but will be correct if we move to a point East of my current location to coincide IST with GMT.
Incomprehensible? Well, it is a little tricky, but this is the only accurate way to tell time at your current location with reference to the world standard time that happens to be relative to Greenwich Mean Time. Now you know how to answer the question, "Is it noon yet?"