(* december 15th 1852; + august 25th 1908) was born in Paris. In 1873 he discovered infrared bands within the solar spectrum. From 1878 on he worked on proofing the magnetic turn of the plane of polarisation of the light in gases. During the 1890ies he examined phosphoric spectra of minerals and uranium salts. That´s where his biggest scientific discovery took place- the evidence of radioactive radiance. Furthermore he was the one to discover the conductibility of the gases that came as a result of the radioactive radiance as well as the observation of ionisation.

In 1899 he recognized the existence of various radioactive kinds of radiance and gave evidence for beta rays being electron currents. Alongside Marie and Pierre Curie he received the nobel prize in physics in 1903.

The unit of radioactive action was given his name in honor of him.

Source: Wikipedia