Today’s Google doodle commemorates a Danish physicist that has not enjoyed widespread fame. Hans Christian Ørsted (aka Oersted), born Aug 14, 1777 was a contemporary and friend of Hans Christian Andersen. In very geeky circles, he is known for observing that electric currents can induce magnetic fields, an important aspect of electromagnetism.
On 21 April 1820, Ørsted made a casual discovery that spurred him to research ithe relationship between electricity and magnetisim. He noticed a compass needle moved from magnetic north when electric current from a battery was switched on and off. Ørsted published his findings, showing that an electric current produces a magnetic field as it flows through a wire.
Want to learn more? Here are some resources:
1) Reproduce Ørsted’s original compass experiment online.
2) Learn more about magnetism with my site recommendations.
3) Wikipedia entry about Hans Christian Ørstedrsted.