What’s the time by your watch?

A huge bell inside a high Clock Tower announces the time everyday. It has been doing so since 1859. The Clock Tower is a part of the Houses of Parliament. River Thames flows nearby. I am sure, by now you have guessed that we are talking about Big Ben, the famous clock situated in London. Since 1924, the British radio -BBC has been broadcasting the chimes of Big Ben to people all over England. It is the most reliable clock in the world. It always shows the accurate time. The time differs by one and a half second to that of Greenwich Meridian Time or GMT. It is the authority that sets the correct international time. GMT also stands for the Greenwich Mean Time.Here Mean is the average time the earth takes to complete one rotation from noon to noon that is 24 hours. It is calculated at the Royal Observatory situated in Greenwich, England. To make things easier, the world has been divided into time zones, each of around 15 degrees of longitude wide. The central zone is at 0 degree longitude. It is the Prime Meridian –the location of GMT.It Marks the starting point of all other time zones. The standard time in each zone differs from the zones of either side by one hour. If you travel to another country, you usually have to alter your watch. The further you go, east or west, the bigger the time change. For example the Indian Standard Time -IST is five hours 30 minutes ahead of GMT. The Clock Tower at Allahabad in Uttar Pradesh, announces IST. Thus the local time of Allahabad is also the IST and is followed all over India. The city is situated at 82.5⁰ E longitude-the exact center of India. So next time if you go abroad, remember to set your watch according to GMT.