It is well known that Birkeland current filaments enter at the poles of Venus (also other planets, but, in context of question lets stick to Venus), forming twin polar vortices, first observed by NASA's Pioneer Venus in 1978 on the north pole and then observed to also be a permanent feature on the south pole by Venus Express in 2006. So, when those paired filaments have passed into the atmosphere through those two holes in the atmosphere, where do they go, exactly?
