Anders Planman also calculated the correct longitude for six locations on the way, among them Kajaani, Mikkeli and Hämeenlinna. He could do this partly because he used surveying tools for his astronomical observations; these were some of the most exact contemporary measuring tools. The minor planet 2639 Planman is named after Anders Planman. Anders Planman Anders Planman (1724 – 25 April 1803) was a Finnish astronomer, professor of physics and mathematician. He was one of the first people to make systematical astronomical observations in Finland. Planman came from a Swedish-speaking Finnish family and his father was a lieutenant. He studied at the
Thomas Henderson (astronomer) is not recorded on the Adie grave; Adie himself died 14 years after Henderson. A blue plaque is installed on his house at 1 Hillside Crescent. It refers to him as "Thomas J. A. Henderson", similar to middle names wrongly added to Wikipedia around 2007. A larger memorial (naming him "Thomas Henderson") is incorporated in the external wall of the City Observatory. Thomas Henderson (astronomer) Thomas Henderson FRSE FRS FRAS (28 December 1798 – 23 November 1844) was a Scottish astronomer and mathematician noted for being the first person to measure the distance to Alpha Centauri, the major component of