Francis William Aston

Born in Birmingham, England in September 1877, Francis William Aston was fascinated by science at an early age. In 1894, Aston attended Birmingham University to study chemistry and physics. Aston won the Forster Scholarship in 1898, allowing him to conduct research that was published in 1901. He began working as an assistant at Cavendish Laboratory in Cambridge in 1909 and conducted research on positive rays. Aston remained at Cavendish until1914 when World War I required his skills at the Royal Aircraft Establishment.

After World War I ended, Aston returned to his studies at Cavendish, now focusing on isotopes. In 1919, Aston made his most significant contribution to atomic science with the

invention of the mass spectrograph. The device was capable of separating isotopes by measuring the minute differences in their masses. Using the mass spectrograph, Aston successfully identified 212 existing isotopes. The invention also prompted him to devise his famous Whole Number Rule which states, "the mass of the oxygen isotope being defined, all the other isotopes have masses that are very nearly whole numbers." The rule became crucial to future developments in nuclear energy technology.

For his accomplishments in the study of isotopes of non-radioactive elements using the mass spectrograph, Aston was awarded the 1922 Nobel Prize in Chemistry. Francis William Aston died in Cambridge on 20 November 1945.