Helium ions from radium
In 1903, the journal Nature reported that helium gas is produced by the radioactive decay of the radium. This key discovery by William Ramsay and Frederick Soddy helped to reveal the structure of atoms. In 1908, Ernest Rutherford confirmed that alpha rays and these radium emanations were one and the same: the nuclei of helium atoms, bearing a positive electrical charge. Each were future Nobel laureates in Chemistry. Ramsey won the Nobel Prize in 1904 for his discovery of the noble gases. Rutherford was recognized in 1908 for his investigations into the disintegration of the elements. Soddy was honoured in 1921 for his pioneering contributions to understanding the chemical properties of radioactive elements such as radium and uranium.[Ref: Ramsay, W. & Soddy, F. Experiments in radio-activity, and the production of helium from radium. Nature, 68, 354 - 355, (1903)]