OLBERS, ty6Ors, HEINRICH WILHELM mAT THXUS (175S-1840). A German physician and astronomer, born at Arbergen, a small village near Bremen. Ile studied medicine at G;?ttingen from 1777 till 1750, and subsequently com menced to practice at Bremen. After 1779 all the leisure time that he could spare from professional occupations was devoted to the study of astronomy. lie first be came widely known through his calculation of the orbit of the comet of 1779, which WaS per formed by him while watching by the bedside of a sick patient. and was found to be very aeeurate. In 1781 he rediscovered the planet l rams, which hail previously been supposed to he a comet. and in 1802 and 1807 respectively discovered the planetoids Pallas and Vesta. Ile also discov ered live comets, in 1798, 1802. 1801, 1815, and 1521, all of which, with the exception of that of 1813. had IWCII some dap; previously observed in l'ariS. ells obseryatimus. ca leulat ions. and not ices of various comets, which are Of value to astrono mers. IVI•Ee published in the 11111rnire of Bode
11782.1829), in the .lanimirr of Eneke and in three eollections by the Baron de Zach. of these calculations were made after a noW method, discovered by himself, for Ileter mining the orbit of the eotnet from three obser vations. It is still employed by astronomers un der the IMMO 1l1hers's 1110t11011: The general equality of the elements of the planetoids led him to propound the theory that the planetoids are fragments of some large planet which former.. Iv revolved r0111141 the sun at a equal to the inenn of the distanees of the planetoids from the same luminary. (fibers also made some important ruseagqhes on the probable lunar or igin of met cork. stones. and invented a inetImd for ealeulating the veloeity of falling stars. Cot suit Schilling, Wilhelm Gibers: &in, Lebo!, and seine Werke (Berlin, 1894).