SCIENCE PHOTO LIBRARY SCIENCE PHOTO LIBRARY
Discovery of radioactivity. This photograph led to the discovery of radioactivity by Antoine Henri Becquerel in 1896. Dark patches show where he put crystals of uranium salt on a photographic plate. His comments are above. Becquerel (1852-1908) was professor of physics at the Ecole Polytechnique in Paris. He put uranium salt on the plate expecting that when exposed to sunlight it would produce X-rays and fog the plate. But since it was cloudy he put the experiment in a drawer; three days later, on 1 March 1896, he developed the plate anyway. It had been fogged by uranium salt alone. Becquerel realised he had found a new form of radiation. He won the Nobel Prize for physics in 1903.
Model release not required. Property release not required.