Comment on “Magnetic field properties of Jupiter's tail at distances from 80 to 7500 Jovian Radii” by M. L. Goldstein, R. P. Lepping, and E. C. Sittler, Jr.

Abstract

As a gedankenexperiment, let us assume that for t < 0 the two discs are at rest relative to one another, separated by a distance small in comparison to their common radius, and threaded by a uniform magnetic field parallel to their common axis (Figure l a). At t = 0, let us spin up the left-hand disc instantaneously to a constant angular frequency fl and accelerate (without spinning) the right-hand disc instantaneously to a speed V away from the other disc. What happens ?The first thing that happens is that the rotation of the left-