Based off of the work of Rutherford, Niels Bohr designed yet another atomic model. By applying quantum theory, Max Planck's theory, to Rutherford's model, Bohr found that electrons, without any lost energy, orbit the nucleus, and do so in energy shells. A electron is placed in these shells based on the amount of energy it contains. However, a shell has a maximum capacity, and, to be stable, must fill shells completely. If an electron gains enough energy, it will shoots to a higher energy shell.