Observed magnetic substorm signatures at synchronous altitude

Journal Article · Tue Jun 01 04:00:00 EDT 1982 · J. Geophys. Res.; (United States)

DOI:https://doi.org/10.1029/JA087iA06p04405· OSTI ID:6805363

Nagaii, T

Magnetic field data from the geostationary satellites GOES 2 and GOES 3 are examined to study the development of substorm activity in the near-earth nightside magnetosphere (around a radial distance of 6.6 R/sub E/). Substorm events are those in which a well-defined single onset is seen at low latitude on the ground. The field configuration change from more taillike to more dipolelike starts initially in a longitudinally localized region in association with the ground onset, and it develops westward and eastward, even when the simultaneous onset of the low-latitude positive bay is recorded in a wide longitudinal region on the ground. It is also found that the variation caused by the field-aligned current starts at the ground onset and reaches a peak at the time of the field change. The present results are consistent with the view that the substorm is associated with a disruption and subsequent conversion of the cross-tail current to the field-aligned current connected with the polar ionosphere. It is indicated that the cross-tail current near synchronous orbit and its disruption are important in producing the field configuration change at synchronous orbit.

• Research Organization: Space Sciences Laboratory, Marshall Space Flight Center, Alabama 35812
• OSTI ID: 6805363
• Journal Information: J. Geophys. Res.; (United States), Journal Name: J. Geophys. Res.; (United States) Vol. 87:A6; ISSN JGREA
• Country of Publication: United States
• Language: English

Related Subjects

640203* -- Atmospheric Physics-- Magnetospheric Phenomena-- (-1987)
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
DISTURBANCES
EARTH ATMOSPHERE
GOES SATELLITES
MAGNETIC BAYS
MAGNETIC STORMS
MAGNETOSPHERE
NIGHT SKY
SATELLITES
SKY