I looked it up on google but saw no answers that differed from the one above. Personally I would have guessed it was an oblique reference to the Northern Lights, myself. They are very easy to miss if you're not out in the middle of nowhere looking at a darkened sky. In fact, the only time I can recall seeing them was when a neighbor in NJ called us to look, and it was barely dusk. I was stunned that we could see them like that in a backyard in suburban NJ.
But hey, the search found me the UEA Sunset Appreciation Society on Facebook, which has some lovely pictures of the campus where I spent a year a long, long time ago.
It was a fairly ugly modern campus, but the grounds it sat on were lovely and I still think with great fondness of all my rambling all over that whole area and Norwich itself. It's very nice walking about when you don't have to worry about bears, wolves, or even mosquitoes.
.
