Could a star have its own heartbeat? It sounds more like poetry than physics, but in the case of a red giant named R Leonis, the answer is a resounding, if slightly erratic, yes.
For over two centuries, we have watched this star. R Leonis is a Mira variable, a type of aging star that pulsates like a rhythmic, celestial heart. It expands and contracts, dimming and brightening with a regularity that makes it a favorite observing target for backyard astronomers and professional researchers alike. We thought we had its rhythm figured out — a little wobble here, a slight drift there, but mostly a steady, predictable drumbeat in the constellation Leo, the Lion.
