A loud enough sound can make a tiny bubble flash with light hotter than the sun's surface

First noticed in 1934 at the University of Cologne, sonoluminescence happens when an intense sound wave makes a gas bubble in liquid collapse so violently it emits a brief flash of light. Inside a single collapsing bubble, temperatures have been measured reaching roughly 12,000 kelvin, hotter than the surface of the sun, though exactly what mechanism produces the light is still debated among physicists.

— Wikipedia contributors, Sonoluminescence — First observed at the University of Cologne, 1934