Science is impressive when something is discovered that cannot be seen. German physicist Willhelm Rontgen working with electrical discharges in glass tubed noticed in 1895 that there was a faint glow on a nearby screen. These rays were invisible and could pass through most materials. He also recorded them on photographic paper and thus the first X-ray image was developed. He quickly realised the medical potential of his discovery. Henri Becquerel discovered radioactivity in 1896 while trying to find more out about X-ray. Marie Cuoir, a Polish born French chemist and physicist and two times Nobel Prize winner, is best remembered for her research into radioactivity and new radioactive element.