(August 14, 1777 – March 9, 1851)
Hans Christian Oersted is the elder brother of Anders Sandoe Oersted who was Danish Prime Minister from 1853 to 1854. Both were prominent during the Danish Golden Age (from 1800 to 1850). Influenced by Immanuel Kant’s ideas of the unity of nature, Hans Oersted believed that natural phenomena were interlinked by some sorts of familial relationships. So, after meeting Johann Wilhelm Ritter (a self-taught German scientist) in 1801, the young Dane bought into Ritter’s idea that electricity and magnetism must have a connection. This conviction prompted him to research deeply into electricity and magnetism. It was not long before he discovered that electric currents actually created magnetic fields. Armed with this evidence, he published a paper which was warmly received by the scientific community. In it, he stated his famous Oersted’s Law, which concluded that a steady electric current creates a magnetic field around it. He was thus recognized as the discoverer of electromagnetism; and his efforts encouraged further researches into electricity and magnetism. It was one of such investigations that enabled André-Marie Ampère to come-up with the formula which illustrated the magnetic forces between conductors that were transmitting electric currents. Oersted’s Law and Faraday’s Law are parts of Maxwell’s Equations, which alongside Lorentz’s Force Law formed the foundations of classical electrodynamics. Besides physics, Oersted joined Humphry Davy in advancing chemistry researches. In his honor, Denmark’s first satellite (launched in 1999) was named after him. Also, the oersted (Oe) represents the unit of auxiliary magnetic field (H) in the centimeter-gram-second system of units (CGS).