born Aug. 14, 1777, Rudkøbing, Den.
died March 9, 1851, Copenhagen
Danish physicist and chemist.
In 1820 he discovered that electric current in a wire can deflect a magnetized compass needle, a phenomenon that inspired the development of electromagnetic theory. His 1820 discovery of piperine, one of the pungent components of pepper, was an important contribution to chemistry, as was his preparation of metallic aluminum in 1825. In 1824 he founded a society devoted to the spread of scientific knowledge among the general public. In 1932 the oersted was adopted as the physical unit of magnetic field strength.