Nevertheless, based on the above analysis, the structure of an atom may be depicted. As shown in Fig. , the electrons must be paired. Two electrons with opposite spinning directions travel in a circular orbit. The orbital diameter is the equilibrium distance Le. If n< 2, the paired electrons move on an isothermal spherical surface. It looks like a flying spin-ring, watching from the nucleus. Since the electron-proton interaction is treated to be equivalent to the electron-electron interaction, i.e., oneto-one, according to Coulomb's law, Le=r. The radius r determines a flying spin-ring's temperature or velocity (ve). Since the flying spin-ring results from the scissor difference of velocities of individual electrons moving on the spherical surface, the electron velocity in the flying spin-ring must equal ve. Two electrons with opposite velocity directions meet to make a ring.