Carbon dating nuclear bomb for friends and dating
The bomb pulse has been declining since the 1963 above-ground test ban treaty, creating a sort of clock they could exploit.
By determining how many radioactive carbon atoms a cell contained, Spalding and Frisén hoped they could calculate its birthdate. Spalding’s curiosity eventually leading her to a slaughterhouse on the outskirts of Stockholm.
Normally, only a tiny fraction of the world’s carbon is 14 C, so little that scientists measure it in parts per trillion. While 14 C concentrations are still low even after the bomb pulse, the difference is obvious to scientists who know what they’re looking for.
To measure the small amounts of 14 C, scientists use a technique called mass spectrometry, which sorts atoms by weight.
Neuroscience dogma had long dictated that the adult human brain did not create any new neurons.
The only time neuron numbers could increase was thought to be during fetal development and early childhood.
A cell’s DNA reflects the amount of 14 C in the atmosphere at the time it was made.
But Spalding persevered, and her hard work eventually paid off.
Last June, she published a paper in which she conclusively stated that adult human did indeed build new neurons in their brains.
Standing outside the low, gray industrial building, she watched as horses went in one side and, about 15 minutes later, a worker appeared on the other end, holding a head, neurons and all.
“It was precisely as revolting as it sounds,” she says.