NOZOMI observation of the interplanetary magnetic field in 1998 Original Research Article

The insertion of NOZOMI spacecraft into interplanetary space, where other spacecraft were operating, added a new array of multipoint observation that extended up to 1.6×106 km in y-direction of the GSE coordinate system. The coherency length of planar magnetic structures has been found to be less than 1.9×106 km in a direction tangential to the discontinuity surface. The region of low coherency seemed to coincide with region of high density plasma. An interplanetary magnetic flux rope which appeared on October 19, 1998, was identical over a distance of 1.9×106 km, while in a high-beta sheath preceding it, the magnetic field appeared differently at separate spacecraft.