Johann Franz Encke

Also found in: Wikipedia.

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.


Gesammelte mathematische und astronomische Abhandlungen, vols. 1–3. Berlin, 1888–89.
Mentioned in ?
References in periodicals archive ?
In jungerer Zeit erschienen die Briefwechsel mit Carl Friedrich Gauss, Johann Franz Encke und Konig Friedrich Wilhelm IV.
It was first recorded by Pierre Mechain in 1786 but was not recognised as a periodic comet until 1819 when its orbit was computed by Johann Franz Encke; like Halley's Comet, it is unusual in being named after the calculator of its orbit rather than its discoverer.
Johann Franz Encke (1791-1865) was director of the Berlin Observatory when Le Verrier's letter arrived on September 23, 1846.
In 1818, however, the German astronomer Johann Franz Encke (1791-1865) worked out the orbit of a comet that had been observed the year before by the French astronomer Jean-Louis Pons (1761-1831).
In the latter he calculated the mean distance between Earth and the Sun to be 149,000,000 kilometers, a remarkable feat and considerably more accurate than the value obtained by Johann Franz Encke using parallax in 1824.
That was some five years before German mathematician Johann Franz Encke was born!
In 1837 Johann Franz Encke, director of Berlin Observatory, repeatedly saw a broad, low-contrast marking in the middle of ring A through the observatory's 9.6-inch Fraunhofer refractor, and he was even able to measure the position of the feature with a filar micrometer.