Magnetic Dynamos (IMAGE) University of Sydney Caption The magnetic fields seen in red giants are left over from an earlier phase when the stellar cores hosted turbulent convection, creating a 'magnetic dynamo'. Magnetic fields are only present in stars more massive than the Sun because core convection only occurs in those stars. Credit University of Sydney 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.