The planetary model was proposed by Rutherford, based on classical electromagnetism, and the main contents are [7]:
① Most of the atom's volume is empty.
② In the center of the atom, there is a very small and dense nucleus.
③All the positive charges of the atom are in the nucleus, and almost all the mass is concentrated in the nucleus. Negatively charged electrons move around the nucleus at high speed in nuclear space.
With the advancement of science, the fact that the linear spectrum of hydrogen atoms shows that the planetary model is incorrect.