We just filmed a molecule bending to the light

For nearly 50 years, scientists knew a tiny light-sensitive molecule called azobenzene could flip between two shapes when struck by light — but nobody had ever seen how it actually moves. A team at South Korea's KAIST, led by chemist Hyotcherl Ihee, finally filmed it, firing ultra-fast X-ray pulses like a slow-motion camera to catch the molecule's central atoms dancing in trillionths of a second. Knowing the exact moves hands engineers a blueprint for materials that respond to light — and even tiny machines that run on it.