Brightness Variations (IMAGE) Max Planck Institute for Solar System Research Caption These are brightness variations of the Sun in comparison with the star KIC 7849521. Credit MPS / hormesdesign.de Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.