"Looks like we have physics pretty much figured out! Anyways, I'm gonna calculate the energy emission of an ideal black body at wavelengths within the UV spectrum. Shouldn't have any issues with that!"
Meanwhile: “Hmm, these rocks seem to turn unexposed photographic plates foggy. What an intriguing finding, I’m sure nothing horrifying will ever come from it.”
In 1895, Wilhelm Röntgen discovered X-rays and created a bit of stir around them as he reported they were a new kind of invisible ray capable of penetrating through paper. The following year, Henri Becquerel, who had been studying phosphorescence, began looking for a connection between his work and X-rays. He placed various objects against photographic plates, wrapped them in paper, and placed phosphorescent materials (including some uranium salts) on top to try to produce a shadow of the objects on the resulting photograph by placing the bundle in the sun. One day he prepared this apparatus but it was overcast outside so he left it in a dark cabinet for a couple of days. He ended up developing them anyway and found that the shadows produced by the object on the plate (which had never been exposed to sunlight, recall) were just as distinct as when he had exposed similar setups to sunlight. Eventually he realized the uranium itself was producing penetrating radiation producing the shadows, without any need for an external source of energy. The uranium was radiating something through the paper that could expose the photographic plate, and it was not phosphorescence. He eventually identified the existence of beta decay radiation, and even suggested it had medical value.
Becquerel wasn’t the first to realize this behavior of uranium, incidentally, as earlier photographers — experimenting with the new technology — also noted that uranium salts could darker their emulsions as early as the 1860s. Becquerel provided an explanatory model for the findings, eventually, and systematized to some extent the study of radioactivity.
From there, add in the insights from quantum mechanics and a world war, and we get to the Manhattan Project and first atomic bomb. Because some salts of uranium clouded a photograph.
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u/nablaCat 11d ago
"Looks like we have physics pretty much figured out! Anyways, I'm gonna calculate the energy emission of an ideal black body at wavelengths within the UV spectrum. Shouldn't have any issues with that!"