What's (Not) Popping? The Long Life and Quick Death of a Marangoni Bubble*

Free-standing films are inherently fragile, unless stabilized with surfactants. Similarly, air bubbles on the surface of a pure liquid are ephemeral, which leads to the intriguing question: Can air bubbles be stabilized in the absence of surfactants? In pursuit of an answer, we discovered a compelling scenario – bubbles at the surface of a pure yet hot oil pool exhibit surprisingly extended lifespans, lasting for tens of minutes or more. I discuss here the nature and origin of this longevity as well as some curious facets of these strangely stable objects.