1786-1853

French Astronomer and Physicist

Dominique Arago was a French astronomer and physicist who, in his scientific career, made important discoveries in the areas of optics, electromagnetic radiation, and served as director of the Paris Observatory. He was also politically active, serving as Minister of War and Marine for the provisional government following the 1848 revolution.

Arago was born in Estagel, France, and studied at the École Polytechnique in Paris, where he became a professor of analytical geometry at the age of 23. Arago's first major contributions to science came in 1811 when, working with Augustin Fresnel (1788-1827), he discovered that two beams of light that are polarized in perpendicular directions do not interfere with each other. This curious result, difficult to explain if light was composed of particles, suggested strongly that light consisted, instead, of waves and had a large...