Photo: Niels Bohr's research notes for his new atomic theory Rutherford's find came from a very strange experience. Everyone at that time imagined the atom as a "plum pudding." That is, it was roughly ...

Niels Bohr's model of the structure of the atom raised the question of how large an atom can be. One hundred years on, the issue is still unresolved. Two physicists discuss the theoretical limits of ...

Niels Bohr introduced what became known as the Bohr model of atomic structure in 1913. The model has since been superseded, but the familiar Solar-System-like structure was based on sound foundations ...