All stars vary in brightness. On geological time scales, main sequence stars become bright red giants and end their lives as dim white dwarfs, neutron stars, or black holes. As stars evolve, some pulsate regularly on time scales ranging from seconds to years. Other stars vary irregularly. SSP scientists study these variations to learn about the structure and life history of stars.
Sallie L. Baliunas, Andrea K. Dupree, Margarita Karovska, Scott Kenyon, Massimo Marengo, Dimitar Sasselov, Willie Soon