Resumen
While we have known for 45 years that a solar-type star's rotation rate and magnetic activity depend on its age (Skumanich 1972), many details still elude us. We cannot yet fully describe the evolution of rotation or activity for stars of a given mass, nor can we use rotation or activity measurements to estimate accurately the ages of isolated field stars. Fortunately, recent technological advances have transformed our ability to observe open clusters, the best laboratories for testing age-dependent stellar properties. We are currently surveying low-mass stars in six open clusters ranging in age from 35 Myr to 3.5 Gyr; here, I focus on our results for the Hyades and Praesepe. These data will allow us to improve our understanding of the age-rotation-activity relation for ≲1M⊙ stars.
