Episode 4 - Henri Becquerel

[Music] everyone knows the history of science is riddled with discoveries that have been attributed to chance but as pastor of said chance favors only the prepared mind on he Biko is one of those scientists whose talent was rewarded by chance he was a brilliant physicist from a family of scientists his father went to Polytechnique he went to Polytechnic and his son went to Polytechnic like his father oh he Beck Hale was interested in fluorescence fluorescence the capacity that some materials have to emit light under certain conditions at the time x-rays had just been discovered x-rays

are invisible and yet photographic paper reacts with them just like with a very intense light but Kyle was interested in this strange behavior of light and so he started to examine it from his point of view as a fluorescence specialist he decided to carry out experiments with a highly fluorescent material called uranium that's right uranium today we have forgotten that this substance was once used because it glowed people even used it to give a bit of color to their crockery without the slightest idea that uranium might have other properties for his experiments Beck hell took

uranium salts conditioned them so that they became highly fluorescent and looked to see if the photographic paper reacted as with x-rays lo and behold it worked he continued his experiments until one day he left non-fluorescent uranium in total darkness together with photographic paper which reacted all the same he realized that the photographic paper was not responding to the fluorescent properties of the uranium but something else radioactivity there the secret is out not only does uranium emit pretty colors after being exposed to light it continuously emits an invisible and powerful ray which no one knew anything

about and that's what was making the photographic paper react the discovery captured the curiosity of young researchers including a certain Mary Curie who decided to make it the subject of her PhD thesis it was such an exciting project that her husband Pierre abandoned his own research on magnetism to work in collaboration with her they couldn't have imagined the effects of radioactivity Pierre and Marie Curie managed to isolate radium an even more active element than uranium make hell took a tiny sample put it in his pocket and ended up with a severe burn Pierre Curie suffered

the same misfortune with his arm on both occasions the wound took six to eight weeks to heal for their research Olli Beck fell and Marion Pierre Curie received the 1903 Nobel Prize for Physics on Lebec he'll died five years later aged just 55 in his honor the Beck hell has been adopted as the unit for measuring the activity of radioactive substances [Music] [Music] you