Low-Energy Hot Plasma and Particles in Saturn's Magnetosphere

• DOI: 10.1126/science.215.4532.571
• Publication Date: 2006-10-05T18:30:32Z
• Authors: S. M. Krimigis; T. P. Armstrong; W. I. Axford; C. O. Bostrom; G. Gloeckler; E. P. Keath; L. J. Lanzerotti; J. F. Carbary; D. C. Hamilton; E. C. Roelof
• Keywords: Magnetosphere of Saturn; Plasma sheet; Magnetosphere of Jupiter

The low-energy charged particle instrument on Voyager 2 measured electrons and ions (energies greater, similar 22 28 kiloelectron volts, respectively) in Saturn's magnetosphere. magnetosphere structure population were modified from those observed during the 1 encounter November 1980 but a manner consistent with same global morphology. Major results include following. (i) A region containing an extremely hot ( approximately 30 to 50 volts) plasma was identified extends orbit of Tethys outward past Rhea. (ii) ion mantle found by extend 7 Saturn radii inside dayside again 2, it considerably hotter volts), there indication cooler < 20 nightside. (iii) At energies 200 volts per nucleon, H(1), H(2), H(3) (molecular hydrogen), helium, carbon, oxygen are important constituents Saturnian presence both H(2) suggests that ionosphere feeds into magnetosphere, relative abundances energetic solar wind origin. (iv) Low-energy 60 electron flux enhancements between L shells Rhea absent encounter. (v) Persistent asymmetric pitch-angle distributions occur outer conjunction torus. (vi) spacecraft passed within 1.1 degrees longitude tube outbound be empty electrons; microsignature Enceladus inbound also observed. (vii) There large fluxes 1.5 million smaller 10 protons 54 orbits Mimas; all sharply peaked perpendicular local magnetic field. (viii) In general, satellite absorption signatures not located at positions predicted basis dipole field models.