In this case, it seems like a desired noise was selectively amplified above signal level to portray an artificially low signal-to-noise ratio, with the article concluding "look at all this noise!"

Still a really neat picture though. Well done. I'm considering buying a print.

I also wonder if knowledge of a star map is sufficient to somehow automatically mask out the stars as the earth rotates, and let the trails show through with less effort, vs masking each trail.