What is the Rutherford scattering experiment and what did it tell us about the nature of the atom?

The experiment involves firing alpha particles, positively charged helium nuclei made of two protons and two neutrons, at a thin layer of gold foil. There is a screen behind the gold foil which is used as a detector to detect any particles that have passed through the foil. The alpha particles are fired in a thin stream at the foil. The results of the experiment showed that most of the alpha particles passed straight through the gold foil, even though it looks as though the alpha particles are being fired at a solid surface. This shows that most of the gold atoms are actually empty space. Some of the alpha particles were deflected slightly, meaning that there must be a small part of the gold atom that is positively charged. This is because the alpha particles are positive and like charges repel each other, so the positive part of the nucleus deflected the alpha particles. A very small amount were deflected by more than 90 degrees meaning this positive part must be very dense. The small, dense, positive centre was named the nucleus. So the Rutherford experiment shows us that atoms have nuclei.