G'day Joybell,

I did flick back through my Astronomy Photo of the Day archives ... but didn't find the "Glory" from a jet (looked like what what David Ingerson described ... but with the shadow of a jetliner projected on the clouds. I guess it was a while back ...

The "dog" in 'rain dog' also somehow suggests that the second rainbow is, somehow, "chasing" the rain back ... I should wade into my Australian National Dictionary (Oxford UP, 1988) to trace the term back.

The "Bee Purple" that experimenters have shown to be an important visual signal to bees is pretty much 'close UV' ... just beyond normal human vision. I guess the flower evolved to signal the bees - without those damn monkeys picking up the signal and spoiling the pollination. I don't think I have any noticeable sensitivity to it ... but have never set out to test it!

I did read that, during WW II, some intelligence signalling was done in occupied areas using close UV frequencies ... and that it was visible to coast watchers whose cataracts had been surgically removed. I don't know if that meant they had to see the unfocussed flashes ... as the thick glass in their spectacles would tend to absorb most of the UV. I must ask Richard Evans (concertina-maker and repairer) whether his (much thinner) implanted lenses, post-cataract, lead to any change at that end of the spectrum ... although I guess they would try to use lens materials that minimised UV - to protect the rest of the eye.

Regards,

Bob