1898 – France
‘1903 – Awarded the Nobel-Prize for Physics jointly with Marie and Pierre Curie’
Stimulated by WILHELM CONRAD ROENTGEN’s discovery of X-rays in 1895, Becquerel chanced upon the phenomenon that is now known as radioactivity in 1896. The Frenchman believed that Roentgen’s X-rays were responsible for the fluorescence displayed by some substances after being placed in sunlight. Although he was wrong to assume that fluorescence had anything to do with X-rays, he tested large numbers of fluorescent minerals.
He found that uranium, the heaviest element, caused an impression on a covered photographic plate, even after several days in the dark, and concluded that a phenomenon independent of sunlight induced luminescence.
Investigation isolated uranium as the cause of the ‘radioactivity’, a name given to the occurrence by MARIE CURIE.
The SI unit of radioactivity, the becquerel is named in his honour.