Here's why:
* Rutherford's Experiment: In 1919, Rutherford conducted an experiment where he bombarded nitrogen gas with alpha particles. He observed that some of the nitrogen atoms were transformed into oxygen atoms, and in the process, a positively charged particle was emitted. This particle, which he named the proton, was later confirmed to be a fundamental particle of the atom.
* Goldstein's Discovery: While Goldstein is credited with the discovery of canal rays (also known as anode rays), which are positively charged ions that are found in a discharge tube, he didn't directly discover the proton.
Therefore, Rutherford is the one who discovered the proton.
