Observations of the flank of Earth's bow shock to −110 RE by ISEE 3/ICE

The ISEE 3/ICE spacecraft made well over 100 crossings of Earth's bow shock between x(SEC) = {minus}20 and {minus}110 R{sub E}, most of them further away than {minus}60 R{sub E}, while resetting its course for comet Giacobini-Zinner. Magnetosonic Mach numbers M{sub MS} normal to the shock in this extreme downwind flank of the bow shock were generally no more than about 60%, often less than 35%, of their values at the subsolar point, so that this set of crossings consists of many examples of low M{sub MS} (M{sub MS} < 3) crossings, including rare quasi-parallel, as well as quasi-perpendicular, cases. The authors tabulate the parameters of the crossings, display some of their magnetic, plasma wave, and spectral profiles at low M{sub MS}, and compare loci of crossings with the extrapolation of a model of earlier statistical success, showing that the model remains useful in the far flank.