Ten transient magnetic structures in Earth's magnetotail, as observed in GEOTAIL measurements, selected for early 1993 at (−) XGSM= 90 ‐ 130 RE, are shown to have helical magnetic field configurations similar to those of interplanetary magnetic clouds at 1 AU but smaller in size by a factor of ≈ 700. Such structures are shown to be well approximated by a comprehensive magnetic force‐free flux‐rope model. For this limited set of 10 events the rope axes are seen to be typically aligned with the YGSMaxis and the average diameter of these structures i
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