The Nautical Almanac & Its Superintendents

1675: The Founding of the Royal Observatory

Royal Observatory 1800

An aquatint view of the Royal Observatory from the north, showing the pavilions as domes rather than cupolas; the dress of the couple in the lower left suggests this item dates to the early 19th century. Inscribed "To the Rev Dr Maskelyne" by his "obliged servant J. Baker".

© National Maritime Museum, London

The Royal Observatory was founded in 1675 by decree of King Charles II (1630-1685). Its foundation was due to a quarrel between John Flamsteed (1646-1719) and Le Sieur de St Pierre over a method of determining longitude. Flamsteed, a meticulous observer and good mathematician, realized that the Frenchman's method was impractical and sent him his observations. St Pierre's response was that the observations were "feigned". However, Flamsteed pointed out that his results were accurate because his catalogue of stars was better than Tycho Brahe's (1546-1601); not only did he have better instruments, but his value for the obliquity of the ecliptic was more accurate!

King Charles II

King Charles II by Sir Peter Lely

© National Maritime Museum, London

King Charles heard about this dispute from his mistress the Duchess of Portsmouth, who was also patron to Le Sieur de St Pierre. He was surprised to learn that Tycho's catalogue of fixed stars was "false" (by more than 10 minutes), and concluded "he must have them observed examined and corrected for the use of his seaman". Not knowing who to appoint, King Charles was advised to appoint "him who informs you". So Flamsteed was appointed as the first Royal

" astronomical observer, forthwith to apply himself with the most exact care and diligence to the rectifying of the tables of the motions of the heavens, and the places of the fixed stars, so as to find out the so much desired longitude of places for the perfecting the art of navigation".

Almost a century was to elapse between the founding of the Royal Observatory (RO) and the first edition of The Nautical Almanac and Astronomical Ephemeris (NA & AE).


Previous Top



HM Nautical Almanac Office © Crown Copyright 2016