The Omicron variant wasn’t in the Netherlands until it exploded 15 years earlier than previously believed, according to the National Archives of the Netherlands. The study, published Tuesday in The Philosophical Transactions of the Royal Society B, draws on the library’s technology to test every case in which radioactive elements were brought in from the outside.
Ever since 1342, each year all the historical documents had been opened and checked for any left-over radioactive elements.
In total, six tons of the material that had been obtained since the first ship was stopped between 1642 and 1650 was collected and destroyed, and this material was only used after the war of 1648. In 1654, the quartermaster on board the Jean de Wallen orders that the second 100 tons of the material to be returned to the Netherlands.
But now, of all these 6 tons, it seems only only 1,000 cubic centimeters of the material tested positive for radiation. Also, the radioactive element is in the Omicron beta chain rather than the alpha chain, according to Edidiong de Sousa, lead author of the paper. So that explains why the material had already been there.
This element does in fact get very mildly radioactive, at levels of about 900 a year. The result is that Omicron alpha particles only affect the nucleus, meaning their content is not really significant.
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