Greenwich Outing. Wednesday, 26th September, 2007.
The Royal Observatory, National Maritime Museum, Queens House
It was a cold and windy morning when 25 members and friends assembled for a 9.30 start as instructed by Ken Robinson our intrepid leader who had arranged for the Club to park at the top of Sainsbury's car park, Kiln Lane, Epsom and soon we were on our way in a new Mercedes coach heading for the M25 via a circular route through Epsom.
We observed on the M25 a massive tailback in the opposite direction and thanked our lucky star that we were not travelling in that direction, soon we were tracking through Greenwich Village to park outside the National Maritime Museum only to find we should have started at The Royal Observatory located at the top of the sprawling site which was within walking up hill distance but a rather longer route by coach, this resulted in confusion about the final pickup point and the subsequent loss of one member!
We soon returned to The Royal Observatory where our splendid driver gave a demonstration of his driving skills entering an iron gate that appeared to be smaller than our coach, but when we opened our eyes we were inside without a scratch but most of us had aged somewhat.
By this time we were passed our eleven o'clock tea/coffee time so Ken lead us inhering to the cafeteria were we regained our composure, then onwards to the Meridian Line (pictured below ....more here) and rooms full of chronometers and nautical instruments, but if you want to have precise details visit the website...here.
We scattered in the various rooms and reassembled at last for the downward slope towards the Museum, with Ken promising that once we had reached the goal, lunch was the prize, but with
Francis in his wheelchair and three members acting as dragging anchors as befits the nautical theme we made the Regatta café where as true Probus members we satisfied our inner needs.
Then onwards to the very spacious and superb displays of naval articles and models, the highlight perhaps being the virtual compass platform that allowed one to pilot a full size ship in real time to perform acts of ship manoeuvres, typically getting out of Sydney harbour in Australia with the roll of the ship very realistic and missing (we hope) the incoming gigantic cruise ships, Ken thought this was great.
The time, that is Greenwich, flashed by and most of the team headed for the coach pickup point, but where was that and where was Kerry?
Our journey home seemed much quicker than our outward journey, but arriving back at Sainsbury's we have to thank our event leader Ken Robinson for a smashing day out, thanks Ken.
The Royal Observatory
Footnote with thanks to the website mentioned above so please visit there is a wealth of interesting details....here
What is a meridian?
A meridian is a north-south line selected as the zero reference line for astronomical observations. By comparing thousands of observations taken from the same meridian it is possible to build up an accurate map of the sky.
The line in Greenwich represents the Prime Meridian of the World - Longitude 0º. Every place on Earth is measured in terms of its distance east or west from this line. The line itself divides the eastern and western hemispheres of the Earth - just as the Equator divides the northern and southern hemispheres.
In 1884 the Prime Meridian was defined by the position of the large “Transit Circle” telescope in the Observatory’s Meridian Building. The transit circle was built by Sir George Biddell Airy, the 7th Astronomer Royal, in 1850. The cross-hairs in the eyepiece of the Transit Circle precisely defined Longitude 0° for the world. As the earth’s crust is moving very slightly all the time the exact position of the Prime Meridian is now moving very slightly too, but the original reference for the prime meridian of the world remains the Airy Transit Circle in the Royal Observatory, even if the exact location of the line may move to either side of Airy’s meridian.
Meridian line laser and Flamsteed house, Old Royal observatory from the grounds of the National Maritime Museum.
Airy's Transit Circle lies at Longitude 0°, by definition, and Latitude 51° 28' 38'' N.
Since the late 19th century, the Prime Meridian at Greenwich has served as the reference line for Greenwich Mean Time. Before this, almost every town in the world kept its own local time. There were no national or international conventions which set how time should be measured, or when the day would begin and end, or what length an hour might be. However, with the vast expansion of the railway and communications networks during the 1850s and 1860s, the worldwide need for an international time standard became imperative.
The Greenwich Meridian was chosen as the Prime Meridian of the World in 1884. Forty-one delegates from 25 nations met in Washington DC for the International Meridian Conference. By the end of the conference, Greenwich had won the prize of Longitude 0º by a vote of 22 to 1 against (San Domingo), with 2 abstentions (France and Brazil).
There were two main reasons for the choice. The first was the fact that the USA had already chosen Greenwich as the basis for its own national time zone system. The second was that in the late 19th century, 72% of the world's commerce depended on sea-charts which used Greenwich as the Prime Meridian.
The decision, essentially, was based on the argument that by naming Greenwich as Longitude 0º, it would be advantageous to the largest number of people. Therefore the Prime Meridian at Greenwich became the centre of world time, and will be the official starting point for the new Millennium.
