On March 1, 1896, Henri Becquerel discovered radioactivity because of bad weather. He'd been testing whether uranium could absorb sunlight and re-emit it as X-rays by placing it on photographic plates wrapped in black paper. But Paris turned cloudy for days so he shoved everything into a desk drawer. When he developed the plates the image was amazingly clear. The uranium was emitting radiation on its own. No sunlight needed. This discovery earned him the 1903 Nobel Prize. 40 years earlier, a photographer named Abel Niépce de Saint-Victor had made the exact same discovery. Nobody cared.