From October to November, ,**the sun became very active. The plural numbers of active region appeared on the solar surface. The most prominent one was the number .20, which yielded extremely large flares X+1/.B at *3/+ UT on October ,2, and X+*/,B at ,*-1 UT on October ,3. These big flares hurled massive coronal mass ejections (CMEs) toward the earth. In this paper the solar-terrestrial relationship during the October super magnetic storms is discussed. Two fast moving clouds of gas from the

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... swept the earth and sparked extreme geomagnetic storms producing the big ground magnetic field depressions of approximately ῌ-/* nT and ῌ.** nT of Dst. Several interesting magnetic field variations observed in interplanetary space and their relationships to the ground magnetic field variations are discussed. Topics are as follows: +) magnetic field polarity changes of the north-south component Bz of interplanetary magnetic field conveyed with the interplanetary coronal mass ejections (ICMEs) and their response to the magnetic field variations on the ground, ,) large amplitude tail flapping motions observed in the distant tail at about ῌ+0* Re, -) large amplitude Pc / oscillations globally observed on the ground during the recovery phase of the super magnetic storm, and .) large amplitude Pc -ULF waves observed in space from upstream through the magnetosheath to the dusk-side outer magnetosphere.