I cam across this picture from the Rosetta mission the other day. You'll notice the sun is illuminating the right hand side of the comet. Additional the tail is coming off the right hand side. This goes against what I've been taught about comets in that the solar wind pushes the tail the opposite direction from the sun. So what's going on here? My personal thought: The FOV is small enough that we don't see the larger tail getting pushed away. Just some local effects from the sunlight. Does that seem reasonable?