In 1911 Ernest Rutherford and his assistants Geiger and Marsden conducted an experiment in which they scattered alpha particles from thin sheets of gold. An alpha particle, having charge + 2e and mass 6.64 x 10-27 kg, is a product of certain radioactive decays. The results of the experiment led Rutherford to the idea that most of the mass of an atom is in a very small nucleus, with electrons in orbit around it—his planetary model of the atom. Assume an alpha particle, initially very far from a gold nucleus, is fired with a velocity of 2.00 x 107 m/s directly toward the nucleus (charge +79e). How close does the alpha particle get to the nucleus before turning around? Assume the gold nucleus remains stationary.