Re: electric field dipole
You are correct unless the dipole forms into a Birkeland Current in a plasma. Birkeland Currents seem to have no such limits. The plasma, called the perfect conductor, allows the free flow of electrons along with their accompaning magnetic fields. Birkeland Currents are scalable from the micro to the macro to the astronomic... litterally.
Nothing much in open space will impede the flow of electrons or protons. Solar material, ionized, is blown off from the sun and flies out into space at great speed where it travels ballistically, perhaps with some direction due to magnetic fields since the material is protons or electrons and charged, and some hits earth’s mag field and may excite the visible aurora. If there is plasma it is near vacuum and the auroral display is an effect of magnetic focusing.
Thunderbolts was on Coast last night. Hope nobody missed it.