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Rutherford's Model

A New Zealand-born scientist, Ernest Rutherford (1871-1937), had been studying alpha-particles since 1898. In fact, he discovered them! In 1909, he was confronted with some rather bizarre alpha-particle behavior that he had to explain. What was the behavior, exactly?

Two of Rutherford's assistants, H. W. Geiger (Germany, 1882 -1945) and E. Marsden (United Kingdom, 1889-1970) performed a now famous experiment in 1909, where they shot alpha-particles from an element called radium at a thin piece of gold foil inside a vacuum scattering chamber.  

They observed the way the alpha-particles reacted when they passed through the foil and hit a zinc sulfide screen (the scintillation in the above figures), which showed small bursts of light through the microscope when struck by the alpha-particles. Surprisingly, not all the alpha-particles went straight through the foil! There were three major findings: