Hans Christian Orsted

    Danish physicist and philosopher Hans Christian Orsted is best known for discoverering the connection between electricity and magnetism known as electromagnetism. Orsted was born in Rudkobing on the Danish island of Lolland. Orsted became interested in science while working as a young boy for his father, Soren Christian Orsted, who owned a pharmacy. Educated primarily through self-study at home, both Orsted and his brother, Anders Sandoe Orsted, went to Copenhagen in 1793 to take entrance exams for Copenhagen University. The brothers passed and distinguished themselves academically at the University. By 1796, Orsted receivied honors for his papers in both aesthetics and medicine.Although he passed his pharmaceutical examination in 1797, Orsted continued his education and, in 1801 received a travel scholarship and public grant that was to profoundly affect his future. With the awards, Orsted spent three years traveling in Europe. 

        In 1820, which Orsted described as the happiest year of his life, Orsted considered a lecture for his students focusing on electricity and magnetism that would involve a new electric battery. During a classroom demonstration,Orsted saw that a compass needle deflected from magnetic north when the electric current from the battery was switched on or off. This deflection interestred Orsted convincing him that magnetic fields might radiate from all sides of a live wire just as light and heat do. However, the initial reaction was so slight that Orsted put off further research for three months until he began more intensive investigations. Shortly afterwards, Orsted's findings were published, proving that an electric current produces a magnetic field as it flows through a wire. This discovery revealed the fundamental connection between electricity and magnetism, which most scientists thought to be completely unrelated phenomena. The result was an intensive effort throughout the scientific community in electrodynamics research, including French physicist André-Marie Ampère's (1775-1836) developments of a single mathematical form to represent the magnetic forces between current-carrying conductors. Orsted's discovery also represented a major step toward a unified concept of energy.

Although some accounts of Orsted's discovery described the event as purely accidental, Orsted's earlier travels in Europe and wide range of studies had drawn him to a believe in the unity of nature, and that a relationship therefore must exist between most natural phenomena, including electricity and magnetism. If Orsted had not been looking for such a relationship, he possibly would not have placed the compass near an electrical current to see if there was an effect. Orsted's discovery, which laid the foundation for the theory of electromagnetism, led toresearch that created much of the technology in common use today, including radio, television, and fiber optics . In honor of its discoverer, the physical unit of magnetic field strength was named Oersted in 1932.

        Among Orsted's continued scientific works, he was one of the first scientists to produce pure aluminum and to conduct experiments in the compressibility of fluids . Orsted had a wide range of interests, including education, philosophy, politics, and literary affairs. Orsted, who married Birgitte Ballum and had eight children, spent over 50 years at Copenhagen University and the Technological College. To the Danish people, Orsted is as much revered for his efforts as a teacher and educator as for his discovery of electromagnetism. His combination of scientific thought and wide-ranging efforts in cultural and political activities helped to transform Danish society. Orsted believed that Denmark would best progress as a country through a close cooperation between research and industry. To help ensure that all of the small country's human resources were fully utilized, Orsted emphasized the need for a comprehensive nationwide system of education and training. At the time of his death in 1851, orsted was head of the Polytechnical Institute at Copenhagen University. In 1993, nearly a century and a half after his death, the first Dutch satellite was named in Orsted's honor.