Why is the Navy so involved in time-keeping?
The earliest users of accurate time were the navy. It was vitally important to aid navigation so an accurate position of ships could be determined. Historic Maritime Greenwich is the centre of time because King Charles II established the first Royal Observatory in the Royal Park at Greenwich in 1675. It was set-up to improve naval navigation. Britain at that time was a strong sea power. The US Naval Observatory (USNO) was established in Washington, DC, in 1830 to co-operate with the Royal Greenwich Observatory to develop accurate time-keeping for the navy. It still is today and the main clock on this site is sourced from the US Naval Observatory in Washington DC.