Antoine Henri Becquerel was a French physicist born on December 15, 1852. He is best known for his discovery of radioactivity, a phenomenon where certain materials emit radiation. This groundbreaking work laid the foundation for future research in nuclear physics and chemistry. In 1896, Becquerel discovered that uranium salts could produce images on photographic plates without any external light source. His findings earned him the Nobel Prize in Physics in 1903, which he shared with Marie Curie and Pierre Curie. Becquerel's contributions significantly advanced our understanding of atomic structure and radiation.