Ernest Rutherford proposed the idea of the planetary model of the atom, where electrons orbit a central nucleus, in 1911. 

The idea of a "planetary electron," where electrons orbit the nucleus like planets around the sun, is attributed to Ernest Rutherford; his model is often called the "planetary model" of the atom. While Bohr later refined this model by proposing fixed energy levels for electrons, the initial concept of electrons orbiting a central nucleus like planets was put forward by Rutherford. The idea of a "planetary" model of the atom, where electrons orbit the nucleus like planets around the sun, was later proposed by Niels Bohr in 1913.