Have you ever been confused about dates being labelled as BCE or CE, or times of the day being quoted as UTC?
They are certainly not what most of us grew up learning at school, so it is easy to see why these terms might cause us to hesitate or, at least, ponder for a moment or two – and maybe more.
If, like me, the dates you were taught at school were either BC and AD, then what exactly do the newer classifications mean? When did they start to be used – and why?
First of all, the traditional BC and AD come from the time that our current Gregorian calendar was adopted in 1582. They are taken, of course, from Before Christ and Anno Domini – Latin for ‘In the Year of Our Lord’. I suppose it is not really surprising that Pope Gregory XIII settled on the supposed year of the birth of Christ as the dividing point.
However, in this age of diverse faiths and secular views, it seems that the Christian based division of history is no longer justifiable or politically correct. So what could be done to make our dates more acceptable to all? Short of developing a whole new calendar?
Easy really, keep the calendar the same but just change BC and AD to something not based on the Christian faith. So, beginning during the 1990s AD became CE for ‘Common Era’ and BCE for ‘Before Common Era’. What could be simpler? The USA still became independent in 1776 but now, instead of AD, it’s CE 1776.
The change is more acceptable to all faiths and it also avoids the confusion as to when Jesus was born. It simply no longer matters.
Of course, if you are a Christian, you can just replace the word ‘Common’ with ‘Christian’. There is a way around everything.
Now it is time to look at UTC. What on earth is that?
We are probably all used to different time zones in various parts of the world. Just to look at a few, for example, the USA has four mainland zones – Pacific, Mountain, Central and Eastern – the UK has one – GMT – while most of mainland Europe is on its own time zone – Central European.
Then we have the issue of putting clocks forward by an hour in the summer, often referred to as daylight saving time. Just to add to the confusion, the USA and Europe start and finish their daylight saving times on different days; Europe in October and USA in November. To be awkward some American states do not alter their clocks at all and in the UK once clocks go forward GMT becomes BST or British Summer Time.
UTC is Coordinated Universal Time, the order of the initials decided by another language. It is the primary time standard by which the world regulates clocks and time. It is, within about one second, mean solar time at 0° longitude, the line that passes through Greenwich, London, and it really is the same as GMT except for scientific purposes. Oh and UTC stays the same, summer and winter.
Pic: The Royal Observatory at Greenwich, UK. The line in the foreground marks the position of the 0° line of longitude that divides the eastern and western hemispheres.