Born Aug. 14, 1777, in Rudkøbing, on the island of Langeland; died Mar. 9, 1851, in Copenhagen. Danish physicist.

Oersted graduated from the University of Copenhagen in 1797. In 1800 he was an assistant at the university, and beginning in 1806 a professor. From 1815 he was perpetual secretary of the Danish Royal Society of Sciences. At the same time, from 1829 he was director of the Polytechnic Institute, which he had founded in Copenhagen. He was also director of the Society for the Promotion of Natural Science, which he had also founded (1824).

Oersted’s principal works were devoted to physics, chemistry, and philosophy. His most important scientific achievement was the establishment of a relationship between electrical and magnetic phenomena in experiments on the deflection of a magnetic needle by current flowing in a conductor. The report on the experiments, published in 1820, prompted considerable research, which culminated in the development of electrodynamics and electrical engineering. Oersted also studied the compressibility of fluids, using the piezometer that he had invented (1822), and he was the first to obtain relatively pure aluminum (1825).

Oersted was an honorary member of the St. Petersburg Academy of Sciences (from 1830).