I work around engines all the time at night and I'm quite familiar with the phenomenon of static electricity discharging from the fan blades which is more common in the winter due to the lower relative humidity. This picture is the first one I've seen on Anet of the phenomenon (I'm sure there are others) and it struck me as unusual because when I've seen static discharge it's not usually localized at the blade tips as on engines 1,2 and 4 on this Qantas bird. It's usually more dispersed across the disc.
It's possible it could be the tips rubbing the abradable shroud but then why only from the 5 o'clock to 7 o'clock positions? Why is it not doing it on nbr 2 engine? Anyone care to float a theory?