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Why is most of an atom empty space?

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Bohr model diagram of a hydrogen atom showing a green nucleus labeled H, a single electron orbit, and text with atomic mass 1.008 and electron configuration 1. — atom The Bohr model describes the structure of atoms, in this case hydrogen.

An atom is considered to be mostly empty space because of the vast disparity in size between its central nucleus and the region occupied by its electrons.12

While the nucleus contains virtually all of the atom's mass, it is incredibly minute compared to the overall volume of the atom. The diameter of an atom is approximately 10,000 to 100,000 times larger than the diameter of its nucleus. To visualize this scale, if an atom were the size of a football field, the nucleus would be comparable to a single marble placed in the center.132

The remaining volume of the atom is essentially unoccupied space through which the electrons move. This structure was famously demonstrated by the Rutherford model, where experiments showed that most alpha particles passed straight through gold foil without deflection, confirming that atoms are composed primarily of open space rather than being solid, impenetrable objects.24