Open AccessThe Jovian auroral oval
Author(s) -
Hill T. W.
Publication year - 2001
Publication title -
journal of geophysical research: space physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/2000ja000302
Subject(s) - magnetosphere , jovian , physics , ionosphere , field line , plasma , geophysics , jupiter (rocket family) , magnetic field , solar wind , outflow , magnetosphere of jupiter , torus , astrophysics , astronomy , magnetopause , planet , geometry , meteorology , space shuttle , quantum mechanics , saturn , mathematics
Jupiter's aurora shows, among other features, a persistent, continuous oval of luminosity that encircles each magnetic pole and maps along magnetic field lines to the middle magnetosphere ( r ≈ 30 R j ). This auroral oval is interpreted here as the ionospheric footprint of the upward Birkeland (magnetic field aligned) current that enforces partial corotation of magnetospheric plasma moving outward from its source (the Io plasma torus) to its sink (the outer magnetosphere and ultimately the solar wind). A simplified model of this current system, based on the assumption of a constant, uniform plasma outflow in a spin‐aligned dipole magnetic field, has a maximum upward Birkeland current density at an ionospheric latitude that maps to the middle magnetosphere. Strong upward Birkeland currents are known, from terrestrial studies, to produce bright aurora.