NPR intern Poncie Rutsch takes a crack at making a big sound. Meredith Rizzo/NPR hide caption

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Shots - Health News

Why Knuckles Crack

A little MRI video seems to settle the decades-old debate about that loud pop of the joints: It's all about bubbles. But imagine an air bag inflating, not the bursting of a balloon.

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Cropland Capture's developers hope players will find where crops are grown amid Earth's natural vegetation in satellite images to shine a light on where humanity grows its food. Courtesy of the International Institute for Applied Systems Analysis hide caption

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