Hans Christian Ørsted

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<tr valign="top"><th style="text-align:right;">Died</th> <td>March 9, 1851
Copenhagen, Denmark</td></tr>

Hans Christian Ørsted
Born	August 14, 1777 Rudkøbing, Denmark

Hans Christian Ørsted (August 14,1777 – March 9,1851) was a Danish physicist and chemist, influenced by the thinking of Immanuel Kant. He is best known for discovering the relationship between electricity and magnetism known as electromagnetism.

Ørsted developed his interest in science while working as a young boy for his father, Soren Christian Ørsted, who owned a pharmacy. He and his brother, Anders Sandoe Ørsted, received most of their early education through self-study at home, and went to Copenhagen in 1793 to take entrance exams for Copenhagen University. The brothers passed and distinguished themselves academically at the University. By 1796, Hans Ørsted received honors for his papers in both aesthetics and medicine.

In 1801, he received a travel scholarship and public grant that enabled him to spend three years traveling in Europe. While in Germany, he met Johann Ritter, a physicist who believed there was a connection between electricity and magnetism. The connection made sense to Ørsted since he believed in the unity of nature and that a relationship therefore must exist between most natural phenomena.

Their conversations drew Ørsted into the study of physics. He returned to Copenhagen University in 1806 after three years of travel and became a professor where he continued his research with electric currents and acoustics. He became the founder of physical studies at the university, and under his guidance the university developed a comprehensive physics and chemistry program and established new laboratories.

While preparing for an evening lecture in April 1820, Ørsted developed an experiment which provided evidence that surprised him. As he was setting up his materials, he noticed a compass needle deflected from magnetic north when the electric current from the battery he was using was switched on and off. This deflection convinced him that magnetic fields radiate from all sides of a live wire just as light and heat do, and that it confirmed a direct relationship between electricity and magnetism.

At the time of discovery, Ørsted did not suggest any satisfactory explanation of the phenomenon, nor did he try to represent the phenomenon in a mathematical framework. However, three months later he began more intensive investigations. Soon thereafter he published his findings, proving that an electric current produces a magnetic field as it flows through a wire. The CGS unit of magnetic induction (oersted) is named in honor of his contributions to the field of electromagnetism.

His findings resulted in intensive research throughout the scientific community in electrodynamics. They influenced French physicist André-Marie Ampère's developments of a single mathematical form to represent the magnetic forces between current-carrying conductors. Ørsted's discovery also represented a major step toward a unified concept of energy.

Ørsted was not the first person to discover that electricity and magnetism are related. He was preceded in this discovery by 18 years by Gian Domenico Romagnosi, an Italian legal scholar. An account of Romagnosi's discovery was published in 1802 in an Italian newspaper, but it was overlooked by the scientific community.

In 1825, Ørsted made a significant contribution to chemistry by producing aluminium for the first time.

On his passing in 1851, Hans Christian Ørsted was interred in the Assistens Kirkegård in the Nørrebro section of Copenhagen.