mar 25, 1936 - 1936 Niels Bohr.
Niels Bohr developed the (Now outdated) Bohr’s atomic model. In this model, it displayed the spectral lines of the path of electrons, and the distance between them. Later in life he became convinced that matter behaved like waves. In 1936 Bohr developed the theory of the Compound Nucleus, which explained how neutrons can be captured by protons.
Added to timeline:
Atomic Theory Webquest timeline