* Astronomy

Jean Baptiste Perrin (30 September 1870 - 17 April 1942) was a French physicist and Nobel laureate.
After Albert Einstein published (1905) his theoretical explanation of Brownian motion in terms of atoms, Perrin did the experimental work to test and verify Einstein's predictions, thereby settling the century-long dispute about John Dalton's atomic theory.
Jean Perrin received the Nobel Prize in Physics in 1926 for this and other work on the discontinuous structure of matter, which put a definite end to the long struggle regarding the question of the physical reality of molecules.
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