Equatorial Rossby mode (IMAGE) Max Planck Institute for Solar System Research Caption The north-south velocity associated with the retrograde propagating mode of oscillation. Left: observations using the SDO/HMI instrument. Right: numerical model. Credit MPS/Z-C Liang 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.