The Noble Prize winner Ernest Rutherford was born on 30 August 1871, in Nelson, New Zealand. His parents, James and Martha had a large family of seven sons and five daughters. Ernest was their second son and fourth child.
At age 15, he obtained a secondary school scholarship to study at Nelson College before moving to Canterbury College (part of the University of New Zealand). He gained three degrees while studying in New Zealand, a BA in 1892 followed by a MA in 1893 and a BSc in 1894. His research projects during this time centered on the field of electromagnetism.
In 1895 with the aid of a grant from the 1851, Exhibition Rutherford left New Zealand to travel to England where he joined Professor J. J. Thomson at Cambridge University’s Cavendish Laboratory as a researcher. At first, he continued his work on electromagnetic waves then switched to studying electrical conduction of gases.
During his study of gases, he exposed gas samples to X-rays and later radioactivity and observe any changes in their electrical conductivity. This led him to his studies of the nature of radioactivity and atomic structure. In 1898, one of his first discoveries in his new field of interest was two types of emissions from radioactive atoms, which he called alpha and beta rays. Soon after this discovery, beta rays were found to be high-speed electrons.
Unable to gain academic promotion in England, Rutherford accepted a post as professor at the McGill University in Montreal Canada in 1898. There, in his own words, he was “expected to do a lot of work and to form a research school in order to knock the shine out of the Yankees!”
Continuing his work on radioactivity his studies of the emissions produced by the radioactive element thorium revealed an isotope of the radioactive noble gas radon. This isotope was known as throron.
With the research chemist Frederick Soddy, he showed that some heavy atoms spontaneously decayed to form slightly lighter atoms so explaining radioactivity.
He also conceived the idea of using the relative amount of differing radioactive isotopes within rocks along with their known half-lives to date geological samples. This method is in use today within the field of earth sciences.
A number of American educational and research centers such as Yale and the Smithsonian approached Rutherford while he was in Canada with offers of posts. While he did not accept any of these offers, McGill University improved his salary to keep him. During his time in Canada, he returned to New Zealand in 1900 to marry Mary Georgina Newton, the daughter of his former landlady.
In 1907, he returned to England to take up the position of Professor of Physics at Manchester University. At Manchester, Hans Geiger with whom he developed the Geiger counter for measuring radioactivity assisted him in his researches. Other research with Geiger and research student Ernest Marsden on the scattering and reflection of atoms striking a thin film of gold foil allowed him to deduce that the bulk of an atom’s mass is concentrated within its nucleus. Danish research student took this a step further producing the accepted model of an atom with negatively charged electron orbiting a dense positively charged nucleus.
Another discovery made while at Manchester was of the nature of alpha waves. Rutherford had suspected they were helium nuclei and this he confirmed.
In 1908, the Nobel Prize Committee awarded him the Noble Prize for Chemistry “for his investigations into the disintegration of the elements and the chemistry of radioactive substances.” Rutherford thought the prize somewhat bemusing as he believed his work was in the field of physics. Although by this time, he was based in England much of the work leading up to the prize was carried out while he was in Canada.
He received a knighthood on 1914 to become Sir Ernest Rutherford.
During the First World War, his research in atomic physics took second place to the more urgent need of finding a method of fighting the growing danger of submarine warfare. To this end, he developed a directional hydrophone. In 1917, when the Americans joined the conflict, Rutherford led a group of scientists and engineers to update the American military services on the latest methods of submarine detection. At the same time, he advised the Americans to utilize their young scientist in the laboratories to develop weapons and defenses in the increasingly technological art of war. Unfortunately, many bright young men went to their deaths in the trenches when his advice went unheeded.
During the horror of the World War, Rutherford hoped that man would not harness the power of the atom until he learnt to live in peace with his neighbors.
Towards the end of the war, Rutherford again turned to the study of atoms. In an experiment using alpha articles to impact atoms of nitrogen gas, he discovered the outgoing protons had greater energy than the original alpha particles. This greater energy came from the transformation of nitrogen atoms into oxygen atoms. This was the first experiment to succeed in the alchemist’s dream of transforming one element into another.
In 1919, he was offered and accepted the directorship of the Cavendish Laboratories and moved back to Cambridge. Under his direction at Cambridge, James Chadwick discovered the neutron while John Cockcroft and Ernest Walton split the atom. To split the atom the pair used a high voltage accelerator to accelerate protons (hydrogen nuclei) before bombarding the target atoms. His team of scientists was also discovered the hydrogen isotope tritium.
Outside of direct research at Cambridge, he campaigned for female students to be accorded the same rights as their male counterparts. His mother-in-law may have influenced his actions, as Mary Newton was the secretary of the Woman’s Christian Temperance Union and a leader of the successful movement for women’s suffrage. This movement led to New Zealand becoming the first country in the world to grant women the vote in 1893.
The New Year’s honors list of 1932 announced his elevation to the peerage and he became Lord Rutherford of Nelson. The event was over shadowed by the death of his only child. His daughter Eileen died shortly after giving birth to her fourth child just before Christmas 1931.
With the rise of Hitler to power in Germany, Rutherford helped found and became president of the Academic Assistance Council. The Academic Assistance Council assisted many non-Aryan scientists in leaving an increasingly hostile Germany, helping them relocate to safer countries principally the USA.
On 19 October 1937, he died in Cambridge. His ashes were buried in the nave of Westminster Abbey close to the tombs of Sir Isaac Newton and Lord Kelvin.
In addition to a number of postage stamps bearing his likeness it appears on the NZ$ 100 banknote. New Zealand is home to the Rutherford Origin, an outdoor exhibition of his life and work in his home town of Nelson.
Within the scientific field the name Rutherford is commemorated. The unit of radioactivity “the Rutherford” and the element rutherfordium (Rf, atomic number 104) both owe their names to this brilliant scientist.
Reference Sources:
Nobel Lectures, Chemistry 1901-1921, Elsevier Publishing Company, Amsterdam, 1966 Nobel Prize.org
BBC Historic Figures
Rutherford.org.nz
