How old are you? Or more precisely, how old are your cells...the cells in your liver, or your spleen, or your brain? It's a question that's harder to answer than you think. That’s because some cells are born after you are, sometimes many many years after, but we’re not really sure which ones, or when — it’s not as if there are cellular birthday parties, marked by balloons and cake. So the question of age remained relatively unanswered until the early aughts, when scientist Jonas Frisén, inspired by work from researcher Bruce Buchholz, had an idea: what if we just look up? In this story, producer Molly Webster travels back in time, to the Cold War; way up into the atmosphere; and deep inside our cells, where a secret little signal, from a very special type of carbon is helping to answer the question: how old are we? But it’s a journey that is pressured by time.
Special thanks to Mark Lovell, Henrik Druid, Laura Kiessling, Phil Newmark, Marc Kirschner, and Thomas Pollard