Antoine Henri Becquerel May 2026

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

Becquerel's most famous achievement was an accidental discovery involving uranium salts. antoine henri becquerel

Beyond the initial discovery, Becquerel’s research advanced the field in several ways: : In 1899, he demonstrated that some radioactive

: 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. : He was the first to realize that

: He was the first to realize that beta particles were identical to the high-speed electrons recently discovered by J.J. Thomson.

: 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.

: Inspired by the discovery of X-rays, Becquerel wanted to see if phosphorescent materials emitted X-rays after being exposed to sunlight.