The other night while measuring faint supernova spectra (2-3 hours exposure) I noticed a bright band in the blue region of the sky background spectrum of my rural sky which I had not remembered being so prominent in the past, so I dug out a similar observation from 2014 for comparison.
The new band in the blue is clear and correlates with the blue peaks found in white LED spectra which vary in wavelength slightly between manufacturers as seen here for example
https://www.nature.com/articles/lsa2015105/figures/5
producing a wide band from ~4350-4550 Angstrom
(Note this is not a quantitative comparison. The spectra are scaled to match the intensity in the continuum around 5000A
Robin
Hi Robin, See attached response from Northumberland County Council.
Paraphrased as, "yes, there's a suspected health issue but it's not as bad as all the others so we're fine". Strange.
My emailed reponse too. To which I got a very terse "go away" reply.
It's on their watch. We know its on their watch. And now they know we know its on their watch.
So does Mr Guy Opperman, the Conservative MP for Hexham... and the local press.
So, "Wi aal knaa noo" as we say up here.