The imaginary line now known as the Greenwich Prime Meridian not only allows us to navigate the globe but also keeps the world ticking to the same symbolic 24-hour clock. But it has not always been so. Until the 19th Century, many countries and even individual towns kept their own local time based on the sun’s passage across the sky and there were no international rules governing when the day would start or finish.
How did Britain get to be the centre of all time and space? The real reason the meridian is at Greenwich is that the Astronomer Royal at Greenwich was the first – indeed, really the only – person to have done the research required to calculate navigational tables. He naturally took his own telescope as the baseline, and once the nautical almanacs which resulted were published no-one could be bothered to do the research all over again merely to establish a different base. It’s important to note that the meridian is at Greenwich, not Charing Cross: so it honours a great scientist rather than Britain. And who was that scientist? None other than Nevil Maskelyne, the villain of Dava Sobel’s popular book Longitude, but arguably the real solver of the longitude problem.
Read the article: At the centre of time