JennyO - the blue moon was clear in the UK (or did I just clean my specs? **BG** )

What is not as well known is the the rods and cones in one's eye work better at different light levels and, in moonlight, in the blue end of the spectrum it the eye more sensitive. So any discolourisation tends to have a more blue in it. Even if the brain can do a good job of compensating.