MAGNETIC NULLS IN THE OUTER MAGNETOSPHERE OF JUPITER - DETECTIONS BY PIONEER AND VOYAGER SPACECRAFT

Citation
Rj. Leamon et al., MAGNETIC NULLS IN THE OUTER MAGNETOSPHERE OF JUPITER - DETECTIONS BY PIONEER AND VOYAGER SPACECRAFT, J GEO R-S P, 100(A2), 1995, pp. 1829-1835
Citations number
11
Categorie Soggetti
Geosciences, Interdisciplinary","Astronomy & Astrophysics","Metereology & Atmospheric Sciences
Journal title
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
ISSN journal
21699380 → ACNP
Volume
100
Issue
A2
Year of publication
1995
Pages
1829 - 1835
Database
ISI
SICI code
2169-9380(1995)100:A2<1829:MNITOM>2.0.ZU;2-C
Abstract
First reported during the Ulysses flyby of Jupiter in February 1992, n ull events are sporadic dropouts in the magnetic field strength detect ed in the outer Jovian magnetosphere, with the magnitude of the field strength decreasing to values that can be less than 0.2 nT. The events occur in regions where the ambient field is primarily southward, that is, aligned with the local planetary dipole field direction and are d istinct from the field depressions encountered in the center of the ma gnetodisk in the middle magnetosphere. They also appear distinct from the field structures encountered at the magnetopause. Here we report a survey of the occurrence of such events in the magnetic field data re corded by the earlier Pioneer and Voyager spacecraft passages through the Jovian system. All of the previous spacecraft to fly through the J ovian magnetosphere recorded field null events on their inbound passes where the field-magnitude dropped below 2 nT. There is little or no e vidence of any field reversal in the center of events. Only Pioneer 11 , which was the only spacecraft to exit on the dayside of the magnetos phere, recorded events on its outbound pass.