ARGELANDER William Friedrich August

ARGELANDER, FRIEDRICH WILHELM AUGUST (Argelander, Friedrich Wilhelm August) (1799-1875), German astronomer. Born March 22, 1799 in Memel (now Klaipeda, Lithuania). In 1822 he graduated from the University of KцІnigsberg. Since 1820 worked as an assistant F. Bessel in Koenigsberg Observatory. In 1823 he moved to Finland. In 1823-1832 - Director of the observatory in Abo (Turku), then to 1836 - in Helsingfors (Helsinki). Since 1837 - Professor, University of Bonn and Director of the University Observatory.

Worked mainly positional astronomy and the study of proper motions of stars. Based on materials of these observations was catalog 560 stars (1835). Analyzing the proper motions 390 stars, has received confirmation of the existence of motion of the solar system in the direction of the constellation Hercules (this idea was first suggested by Herschel V.). In 1843 published an atlas and catalog of all stars visible to the naked eye. In 1838 Argelander began observations of variable stars and these observations led to 1870. Received more than 12 000 light count about 40 such stars, opened a large number of new, introduced their range. In 1852-1859 oversaw the creation of "Durchmusterung" (Bonner Durchmusterung) (publ. in 1859-1862, reissued in 1950) - the catalog and atlas of all the stars of the sky in the Northern Hemisphere brighter than 9-th magnitude (324 188 stars).

Died Argelander in Bonn, February 17, 1875.