New Zealander-English physicist who was born in Nelson, New Zealand, attended school in Nelson and Marlborough, and finished his tertiary education in Canterbury, New Zealand before traveling to England. Rutherford is best known for devising the names alpha, beta, and gamma rays to classify various forms of "rays" which were poorly understood at his time (alpha and beta rays are particle beams, while gamma rays are a form of high-energy electromagnetic radiation ).

Rutherford deflected alpha rays with both electric and magnetic fields in 1903. He also observed that the intensity of radioactivity fell off with time, and named the halving time the "half-life. " In 1906, his students Geiger and Marsden conducted the classic gold foil alpha particle scattering experiment which showed large deflections for a small fraction of incident particles. This led Rutherford to propose that the atom was "nuclear." For his discoveries, Rutherford was awarded the 1908 Nobel Prize in chemistry. He much resented that the prize was in chemistry rather than physics, and his acceptance speech made a remark to the effect that he had seen many transformations in his studies, but never one more rapid than his own from physicist to chemist.

Rutherford suggested that the simplest possible rays must be those obtained by hydrogen and that these must be the fundamental positively charged particle, which he dubbed the proton in 1914. In 1917, he passed alpha particles through a gas of nitrogen and occasionally observed scintillation of hydrogen impacting on his screen. He concluded that the alpha particles were knocking protons out of the nitrogen atoms, and thus that he had made the first observation of nuclear reactions.

Rutherford's image appears on New Zealand's $100 note, that country's largest denomination of paper currency. One particularly memorable quote attributed to Rutherford is "All science is either physics or stamp collecting" (Birks 1963).