Johann Franz Encke(redirected from Johann Friedrich Encke)
Encke, Johann Franz
Born Sept. 23, 1791, in Hamburg; died Aug. 26, 1865, in Spandau, now part of Berlin. German astronomer.
Encke graduated from the university in Göttingen. Beginning in 1816 he worked at the observatory near Gotha. From 1825 to 1863 he was director of the Berlin Observatory. During the same period, from 1828 to 1863, he was publisher of the Berliner astronomisches Jahrbuch, Encke studied the motion of the comet 1818, for which he detected secular acceleration of the mean motion, and established its periodicity.