Donald Sadler

Donald Harry Sadler (22 August 1908 – 24 October 1987) was an English astronomer and mathematician who developed an international reputation for his work in preparing astronomical and navigational almanacs. He worked as the Superintendent of His Majesty's Nautical Almanac Office from 1937 to 1971.

Early life Donald Sadler was born in Dewsbury, Yorkshire, on 22 August 1908. He attended the local grammar school where he excelled in mathematics. He studied mathematics at the University of Cambridge and received a first-class degree in 1929.

Donald Sadler oversaw the transfer of the Nautical Almanac Office within the Royal Greenwich Observatory from the control of the Admiralty to the new Science Research Council. He served as general secretary of the International Astronomical Union (1958–1964), then as vice-president, and president (1968–1970) of the Council of the Federation of Astronomical and Geophysical Services.

Later life Donald Sadler retired as Superintendent of the Nautical Almanac Office in 1971. He continued working at the office for a further year, retiring in February 1972. Sadler continued with his activities in the Royal Institute of Navigation.

Donald Sadler died at Bexhill-on-Sea, East Sussex, on 24 October 1987.