Flamsteed | John | 1646-1719 | 1st astronomer royal

Biographical Information

Occupation, Sphere of Activity

John Flamsteed (1646-1719) was the first astronomer royal of England. His legacy to the science of astronomy was mostly in more accurate mapping of the skies, rather than radical new theories. He had limited formal education, having left Derby Free School due to ill health, but he did benefit from tutoring, and his illness led to his first experience of astronomy: unable to attend school, he observed the partial solar eclipse of 12 September 1662.

Flamsteed's favour with the King improved dramatically in the winter of 1674-1675, when a French courtier of Charles II suggested a method of calculating longitude, accurate knowledge of which is crucial for safe navigation. Flamsteed demonstrated that the theory was impractical due to the inexactitude of existing stellar measurements, which had not been refined since the time of Tycho de Brahe (1546-1601), before the time of telescope when telescopes were not used. For a seafaring nation like England, safe navigation was crucial, and Flamsteed's proof of the stellar tables' inaccuracy was noted. Plans to establish a royal observatory, which had been semi-dormant for some time, were rapidly revived, and Flamsteed was appointed as the first astronomer royal (specifically ordered to make observations relevant to navigation), and the Greenwich Observatory was constructed.

Though he was underpaid, his observatory underfunded, and the initial government enthusiasm for astronomical matters was short-lived, Flamsteed set to work making his observations. He used a new method of defining stars' positions, which radically improved accuracy. The uncertainties and errors in these measurements were smaller than those in Tycho de Brahe's (admirable) results by a factor of fifteen. His discoveries elicited the curiosity of fellow astronomer Edmund Halley (1656-1742) and physicist Isaac Newton (1643-1727).

Flamsteed always had a deep dislike for Halley - probably because of their conflicting personalities more than simple professional rivalry - but initially had friendly relations with Newton. However, as Newton insinuated himself more and more into Flamsteed's work (he needed Flamsteed's observations of the Moon to establish his theories), their relations deteriorated. Eventually, Halley and Newton conspired to publish Flamsteed's work (as the Historia Coelestis), against his expressed wishes (the data was incomplete and not yet up to his high standards of accuracy). Flamsteed and Newton's feuding - particularly Newton's arrogance and Flamsteed's obstruction of Newton's quest for information - had a negative impact on the progress of science, Newton having abandoned some of his studies of the Moon because of Flamsteed's refusal to provide data on its orbit.

Flamsteed's least celebrated 'achievement' was to 'prove' stellar parallax, a problem which had obsessed astronomy since Copernicus had suggested the heliocentric system. His 'discovery', however, was worthless; the altered positions of the fixed stars were due to aberrations in the light of the stars that he observed. His error was so precisely noted, however, that the precise nature of the aberrations can now be precisely computed.

The complete, authorised version of Flamsteed's observations was only published posthumously (completed by his assistants) as the Historia Coelestis Britannica, including data on the positions of nearly 3000 stars - including a number of sightings of Uranus, which he believed to be a fixed star.


John Flamsteed had a stormy working relationship with Edmund Halley and Isaac Newton.

Other Significant Information

Notable publications:

Historia Coelestis (1712)

Historia Coelestis Britannica (1725)

Honours, Qualifications and Appointments

1674: Awarded Master of Arts by letters-patent, University of Cambridge

1675: Appointed Astronomer Royal

1675: Ordained as Priest

1677-1709: Elected Fellow of the Royal Society


List of sources for the biographical information:

Gillispie, Charles C, Dictionary of Scientific Biography, vol V, (New York, Scribner's,1972)

Lee, Sidney, Dictionary of National Biography, vol VII, (London, Smith, Elder & Co, 1908)

Encyclopaedia Britannica, vol 9, (Chicago, William Benton, 1964)