jan 1, 1909 - Ernest Rutherford

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-1871 - 1937, New Zealand
-In 1909 proposed a nuclear model of the atom in which: a very small positively charged nucleus containing most of the mass of the atom; a very large volume around the nucleus in which electrons move; a nucleus containing positively charged protons; a number of protons equal to the number of electrons. He later postulated the existence of a neutral particle in the nucleus to make up for the calculated mass deficiency in the atoms studied.
-Most alpha particles passed through the gold foil suggesting that an atom is largely empty space. Some alpha partcles were deflected significantly suggesting that the positive charge of an atom must be concentrated in a very small sphere.

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