Well, yes ... it must be very thin indeed, because it exerts no discernable drag on any body in the solar system. So thin, in fact, that one wonders how something so thin could produce these circuits at all.
It's not clear how a comet could be an "electrical discharge," either ... though perhaps in his attempt to be all technical sounding, the author skipped a few important words...?
Why yes it is so thin that reputable scientists and engineers are designing space craft that use it for propulsion with huge Mylar sails. We do see evidence of this plasma and its effects. The aurora borealis is a prime example.