It seems like the pillar is lit from an angle? Is this an artifact of some other phenomena (eg higher density being at the same side of the pillars) or is there a nearby star shining on it?
The most recent image is near-infrared light (per the captions), so the parts of the image that look brightest are where the most near-infrared light is. Also, it's a star nursery, so areas brightest are (I believe) where the new stars are forming. If they're the biggest source of near-infrared light in the area, that would explain the lighting angles.