Macro- and micro-structure of the interplanetary magnetic field

Abstract

A radial gradient of the interplanetary magnetic field between 0.81 and 1.0 AU has been observed in agreement with Parker's model. The average magnitude of the magnetic field component perpendicular to the ecliptic plane was zero during 1966.Discontinuities in the direction of the magnetic field were observed when viewing on a scale of one hour; directional distributions are presented which describe the topology of these discontinuities. It was found that sometimes a large, discontinuous change in the field direction was accompanied by a dip in the field intensity; the measured minimum magnetic field intensity agrees with the value calculated from the hypothesis that the dip was the result of magnetic field annihilation. At least two of these "D-sheets" appear to be transitional regions associated with tangential discontinuities.