Rutherford's Conclusion experiment

If you are talking about the Gold-foil experiment:

During Rutherford's time, the JJ Thomson (plum pudding) model was the accepted version of an atom. However when Rutherford shot positive alpha particle rays at a piece of gold foil. Some of the particles bounced back, meaning that Atoms had a positive center. Most of the particles went through, which means that Atoms are mostly empty space.