Encke's Comet

(ěng'kāz.) (Ast.) A well-known comet of short period, the first of the cla ever recognized. It was discovered by Pons, at Marseilles, 1818; but was named after Johann Franz Encke, a German astronomer, B. at Hamburg, 1791, who established the periodic character of this body's motion; also detected the fact that its succe ive returns to perihelion at intervals of rather more than 1,211 days, are accelerated by a short interval of time, from which circumstance he was led to conclude that the comet's motions are retarded(and so its period shortened) by the resistance of an etherial medium. [s. 330]