The Jovian magnetotail

Abstract

This paper will review the present state of knowledge of plasma, magnetic field and plasma wave characteristics of the Jovian magnetotail, near Jupiter and to distances as great as 9,000 Jupiter radii, and from both the large and small scale perspectives. Our knowledge of Jupiter's tail, especially the distant tail, comes primarily from data from five experiments onboard Voyager 2, some of which will be presented. The Jovian tail has many unusual properties, such as the large scale sausage-string shape of its outer boundary, but shares some important properties with earth's magnetotail, such as a central current sheet and a surrounding region resembling a plasma sheet consisting of hot ions ( E > 28 keV). This new interpretation of the existence of a “plasma sheet” clears up the dilemma of the so-called core regions, which we will discuss. There is a significant flow of plasma of solar wind origin in the distant tail lobes having (tailward) speeds and densities suggestive of boundary layer plasma. We will discuss tail size, estimated magnetic flux content, degree of field helicity, magnetic turbulence (in near vs. far tail regions), and evidence for the tearing away of the tail (probably by field reconnection) at the time of an interplanetary magnetic sector boundary passage.