Glow-in-the-dark objects seem magical when you’re a kid—they can brighten up a dark room without the need for electricity, batteries or a light bulb. Then at some point you learn the science behind this phenomenon. Chemical compounds called chromophores become energized, or excited, when they absorb visible light. As they return to their normal state, the stored energy is released as light, which we perceive as a glow. In materials science, researchers rely on a similar phenomenon to study the structures of materials that will eventually be used in chemical catalysis, batteries, solar applications and more.