A magnetic cloud with unusual structure and bow shock movement observed on May 13, 1995 Original Research Article

A magnetic cloud embedded in a corotating interaction region was observed by WIND 244 Re upstream of Earth on May 13, 1995. This cloud was unusual since it had at least two internal structures and the profile of the magnetic field strength did not conform to a simple force-free flux rope model, though the field direction fitted well. About 90 min later, it was detected by IMP 8 and GEOTAIL in front of Earthʹs bow shock. GEOTAIL observed a sunward movement of the bow shock 8 min after the passage of the front boundary. From the normal vector of the bow shock front, we deduce that the shape of the expanding bow shock was distorted from an axially symmetric geometry. The shape was consistent with distortion due to the observed inclination of the front boundary of the magnetic cloud.