Hello & welcome to this week’s GK Nugget.
October 13 marks the day on which the Greenwich (pronounced
Gren-itch, not Green-which) Meridian in UK was established by the International
Meridian Conference in 1884 as the starting point for measuring time zones
across the globe.
So on its 132nd
anniversary, we’re going to look at why it was important to establish GMT in
the 19th century, why it’s still significant and also at some quirky
facts about time.
GMT was born at the world-famous Royal Observatory in
Greenwich, London, established in 1675 by Charles II. According to the
Observatory's website, the site "is, by international decree, the official
starting point for every new day, year and millennium". The growth of
shipping & railroad travel led to great confusion about the correct time at
different parts of the globe which made it necessary to establish the prime
meridian.
The Greenwich Meridian maintains a position of Longitude
0,0,0 and Latitude 51, 28, 38N (North of the Equator). Timezones are established
based on how far east or west (so longitude is used as a measure) a country is
from the Greenwich Meridian.
Although GMT and UTC (Coordinated Universal Time) share
the same current time in practice, GMT is a time zone officially used in a
majority of European and African countries, while UTC is not a time zone, but a
time standard that is the basis for civil time and time zones worldwide. This
means that no country or territory officially uses UTC as a local time.
Also, UTC is based on atomic time and is far more
accurate than the reliance of solar time from a particular spot on the Earth’s
surface.
Neither UTC nor GMT ever change for Daylight Saving Time
(DST). However, some of the countries that use GMT switch to different time
zones during their DST period. (e.g. UK uses British Summer Time (BST), which
is one hour ahead of GMT, during the summer months).
Daylight Saving Time is used to save energy and make
better use of daylight. It was first used in 1908 in Thunder Bay, Canada.
Germany became the first country to introduce DST when
clocks were turned ahead 1 hour on April 30, 1916. The rationale was to
minimize the use of artificial lighting in order to save fuel for the war
effort during World War I.
We all know that India is 5.30 hours ahead of GMT, but
Nepal is 5.45 hours ahead while Chatham Island (New Zealand) is 12.45 hours ahead of
GMT & Western Australia is 8.45 hours ahead.
Usually, when one travels in an easterly direction - a
different time zone is crossed every 15 degrees of longitude (which is equal to
one hour in time – 24 hours multiplied by 15 degrees gives us a 360 degrees globe),
except in Japan which is 2 hours behind Vladivostock which is to the West of
Japan.
Most of mainland Spain is either on the same longitude as
or further west than the UK. And yet, Spain is an hour ahead, time-wise.
Prior to 1995, International Date Line split the country
of Kiribati. The result was that the eastern part of Kiribati was a whole day
and two hours behind the western part of the country where its capital is
located. In 1995 Kiribati decided to move the International Date Line far to
the east- which placed the entire country into the same day.
Although Russia is geographically spread over 11 time
zones, it officially observes only 9 time zones (from March 2010).
China observes one time zone UTC/GMT + 08:00 - which
makes this time zone uncommonly wide. In the extreme western part of China the
sun is at its highest point at 15:00, in the extreme eastern part - at 11:00
The International Space Station uses UTC/GMT.
Unfortunately, Dr Emmett Brown & Marty McFly famous
DeLorean time machine hasn’t become a reality yet so the only time travel that
we’ll be doing for a while is traversing across time zones.
That’s all on this weekend’s GK Nugget.
