Ernest Rutherford conducted the gold foil experiment in 1909. This crucial experiment aimed to investigate the structure of the atom, and it ultimately led to the discovery of the atomic nucleus.
Rutherford and his team directed a beam of alpha particles at a very thin sheet of gold foil. They observed that while most of the particles passed straight through the foil, a small fraction were deflected at various angles, and some even bounced back. This unexpected result indicated that the atom consists mostly of empty space, with a dense core at its center—what we now know as the nucleus.
This experiment fundamentally changed our understanding of atomic structure and laid the groundwork for modern atomic physics.