Premium
Energetic particle signatures at Ganymede: Implications for Ganymede's magnetic field
Author(s) -
Williams D. J.,
Mauk B. H.,
McEntire R. W.,
Roelof E. C.,
Armstrong T. P.,
Wilken B.,
Roederer J. G.,
Krimigis S. M.,
Fritz T. A.,
Lanzerotti L. J.,
Murphy N.
Publication year - 1997
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1029/97gl01931
Subject(s) - jovian , magnetosphere , jupiter (rocket family) , physics , galilean moons , icy moon , astrobiology , magnetic field , galileo (satellite navigation) , polar , geophysics , satellite , natural satellite , magnetopause , saturn , astronomy , solar system , planet , geology , geodesy , space exploration , quantum mechanics
The second encounter of the Galileo satellite with the Galilean moon Ganymede provided energetic particle measurements showing effects due to the presence of that moon. Jovian corotation signatures, present on approach to and departure from the Ganymede system, suddenly become much smaller when Galileo enters what has been termed Ganymede's magnetosphere. The location of these transitions agrees with magnetopause crossings identified by the magnetometer and plasma wave instruments. In Ganymede's magnetosphere, energetic ion and electron distributions display loss cone signatures whenever the Energetic Particles Detector (EPD) views along the magnetic field line. The loss cone measurements are used to estimate Ganymede's surface magnetic field along the satellite track. The results agree with model projections to Ganymede's polar cap and support the existence of a Ganymede‐intrinsic magnetic field. An evolution from single to double loss cone also occurs with increasing electron energy.