Multipoint observations of global magnetospheric compressions

摘要: The magnetic field experiment on the Viking satellite detected long-period compressional oscillations with amplitudes ranging from 2 to 5 nT and periods 7 23 min nine orbits covering a wide range of polar subauroral latitudes during period March August 1986. We present case study an event June 18, 1996, in which similar pulsations were also observed by global network more than 50 ground magnetometers GOES-5 GOES-6 spacecraft. variations throughout auroral, midlatitude, equatorial regions, at Viking, GOES-5, approximately phase, whereas some morningside stations half-wave out phase. interpret these as evidence for periodic compressions inflations magnetosphere driven solar wind pressure pulses. relative time delays peak GOES-6, ground-based are consistent originating prenoon magnetopause whose signatures spread both poleward antisunward sides local noon.