The Royal Observatory Greenwich marks its 350th anniversary today, commemorating its founding by King Charles II in 1675. Initially tasked with solving “the longitude problem” – a crucial challenge in maritime navigation due to the difficulty in precise timekeeping during long voyages – the observatory has played a pivotal role in establishing accurate east-west positioning.
Under John Flamsteed’s leadership, meticulous observations of the Moon and stars helped rectify celestial tables, paving the way for improved navigation. The introduction of the Greenwich Time Ball in 1833 further enhanced the observatory’s capabilities, providing a visual signal that sailors could use to synchronize their chronometers.
Today, the Royal Observatory is renowned as the home of time and navigation, with its Prime Meridian established in 1884 as the world’s zero longitude. The observatory’s legacy has endured through 14 successive astronomers royal who have advised monarchs on various scientific matters, although their modern role remains largely honorary.
Source: https://www.astronomy.com/today-in-the-history-of-astronomy/june-22-1675-the-royal-observatory-greenwich-is-founded