Turn (angle)
As turn (engl. "Rotation", ie törn ) is in the English language, a square for instrument engineering and military affairs referred whose unit the full rotation is. A turn can be divided into half turn, quarter turn, etc., into 2 n parts as well as 100 centiturns or 1000 milliturns. The British astronomer Fred Hoyle proposed a decimal subdivision down to the microturn (about 1.3 ") in 1962 , but this was hardly ever used. Individual measuring devices for artillery and satellite observation are, however, divided according to milliturn .
1 turn (a full angle ) corresponds to 360 °, 400 gon or = 2 π rad . In German, the dimension is called full angle. Some pocket calculators support the turn under the unit symbol “tr”, e.g. B. from the HP 39gII and since 2011 from the HP Prime . The analog unit “pla” for plenus angelus (proposed in DIN 1315 from March 1974) could not, however, gain acceptance.
See also
literature
- Nelson Hayes: Trackers of the Skies (History of the Smithsonian Satellite-tracking Program) , Howard Doyle Publishing Comp., Cambridge (Mass.) 1968 and Academic Press 1975
- Friedrich Schiffner: Determination of satellite orbits . In communications from the Uraniasternwarte, Vienna 1965