Scientists Finally 'See' a Proton Move Through Water, and It Only Took 200 Years

For over two centuries, scientists have known that water transports a positive charge through protons. But they had never actually seen it happen—until now.

In a Science paper published September 11, Yale researchers reported that they devised a method to track, measure, and effectively “see” a proton’s journey through water. For the experiment, the team used a 30-foot-long mass spectrometer—an instrument that separates different elements by mass—that took years to customize and refine. The device allowed them to benchmark how quickly protons moved through six charged water molecules.

“We show what happens in a tiny molecular system where there is no place for the protons to hide,” said Mark Johnson, senior author of the study and a chemist at Yale University, in a release .

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