For the first time, astronomers have observed a star pulsing in response to its orbiting planet. The star, HAT-P-2, pictured, is one of the most massive exoplanets known today. The planet, named HAT-P-2b, tracks its star in a highly eccentric orbit, flying extremely close to and around the star, then hurtling far out before eventually circling back around. (Image: courtesy of NASA, edited by MIT News)
