Acceleration and Guidance of Ions and Electrons Along Field Lines (Diagram)

Image credit: Lundin, et al / Mars Express / ESA

Original caption:
Cusp / cleft aurora is expected to occur between adjacent anomalies and halo aurora circumscribing the large-scale region of crustal magnetization.

(Plasma Acceleration above Martian Magnetic Anomalies)
http://www.irf.se/link/Science_paper_feb06

Note: Does the motion of ions in one direction and electrons in he opposite direction along magnetic field lines constitute a field-aligned electric current with bi-directional flow?

(Field-aligned current)
http://www.plasma-universe.com/index.php/Birkeland_current

(Which Way Does the "Electricity" Really Flow? William Beatty, 1996.)
http://amasci.com/amateur/elecdir.html