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Spotlight: Radiometric Dating

Credit: R. Wilson/NIST

Dating can be complicated. Our team uses this instrument — a live-timed anticoincidence counter — to figure the decay rate of an isotope, which we can then use to determine an object’s age in the geological history of our planet (through a process called radiometric dating). Encased in 6,350 kg (14,000 lbs.) of lead blocks to shield from external radiation, its two levels of detection make this one of the most precise instruments for radioactivity measurements at NIST. Right now, our team is preparing to better measure the decay of iodine-129, which could expand dating capabilities beyond carbon’s 50,000 years to 160,000,000 years. That’s a lot of history we’ll be able to account for.

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Released February 14, 2020, Updated December 23, 2020