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This is Scientific American's 60-Second Science, I am Karen Hopkin. This will just take a minute.

Bubbles. Big ones entertain children and tiny ones tickle¹ champagne² aficionados³. Even witches appreciate what they bring to a boiling cauldron. If you, too, are a bubble lover, then you’ll enjoy this latest bubble study published in the journal Nature. In it, scientists show that a bursting bubble can leave in its wake a ring of smaller bubbles, a finding that could have implications for disease transmission.

Bubbles are engaging because of their effervescence. Here one minute and then [popping sound] they’re gone. Or so we thought. What the new study shows, however, is that when bubbles break open on the surface of a liquid or solid, they don’t simply disappear.

Using high-speed videography, scientists observed surface bubbles as they burst. And they saw that when the skin of the bubble ruptures⁴, it retracts⁵. As this film folds in on itself, it can trap air, thus forming smaller, daughter bubbles. These daughters can then do the same, leaving behind a generation of grandbaby bubbles. And so on.

The tinier the bubbles, the greater their internal pressure. So when these babies blow, they can disperse⁶ their contents far and wide. Which is fine if you’re sipping⁷ champagne. But less welcome in a hot tub that might be full of cold and flu.

Thanks for the minute for Scientific American's 60-Second Science. I am Karen Hopkin.