Electric arc in 0 gravity? Curved or straight?

[Nidum]

The shape of arcs may be influenced by the relative alignment of the faces of the two electrodes .

Electrode faces which are both angled up do seem to produce upward curved arcs .

 

[jaropat]

The shape of arcs may be influenced by the relative alignment of the faces of the two electrodes .

Did You see arc curving down? The heated air in the plasma rises up and the least resistance between electrodes remains through the plasma arc.

 

[jaropat]

Yeah big one, but why?

Very long arc is shaped at air movement and the least resistance between electrodes remains through the plasma arc.