Antoine Henri Becquerel 95%

: Days later, he developed the plate and found a clear, dark image of the crystals—meaning they were emitting "penetrating rays" spontaneously, without any external energy source like the sun.

Antoine Henri Becquerel (1852–1908) was a Nobel Prize-winning French physicist renowned for his discovery of . His work laid the foundational stone for nuclear physics and changed our understanding of the atomic structure. The Discovery of Radioactivity (1896) antoine henri becquerel

: Inspired by the discovery of X-rays, Becquerel wanted to see if phosphorescent materials emitted X-rays after being exposed to sunlight. : Days later, he developed the plate and

Becquerel's most famous achievement was an accidental discovery involving uranium salts. The Discovery of Radioactivity (1896) : Inspired by

Beyond the initial discovery, Becquerel’s research advanced the field in several ways:

: On a cloudy day in Paris, he placed uranium crystals on a photographic plate wrapped in black paper and tucked them in a dark drawer.

: In 1899, he demonstrated that some radioactive rays (beta particles) could be deflected by magnetic fields, proving they were charged particles rather than waves.