Thursday 25 June 2009

Night Shining

Over the years I've been fascinated by various natural optical phenomena that can be seen. Sundogs and halos, parhelic arcs and circumzenithal arcs have been seen over the years (the last of those is great by the way, looking like an upside down rainbow grinning at the top of the sky). Of course manyh rainbows have been seen. Single, double, partial and the last one looked like it was going down into the valley we were driving into. Moon halos are harder to see in that you need a dark sky and bright moon as well as the right conditions for halo formation.

I've managed to see aurorae from home, nothing spectacular but certainly green glowing in the sky where normally there isn't any.

Once thing I've not seen for certain is Noctilucent Clouds. Not till over night tuesday/wednesday anyway. Over the years during the summer months if I've woken in the night then I'll have looked out of the window at the back towards the north to see if any were there. Often I did think I could see something but was never sure if what I was looking at was noctilucent clouds or just a slightly woozey addled brain making up what I wanted to see when I'd just woken up.

Overnight I woke up again and after dealing with what needed dealing with I thought tonight would be a good night for looking out to see noctilucent clouds. The night had started quite still and very clear and would have been great for stargazing had it not been just after midsummer. At about 2 in the morning though the sky had gone as dark as it could get. I stepped out into the garden and looked towards the north and northeast. There for a few degrees above the horizon was a blueish, whitish glow. Within the faintly glowing area there was some form of cloud like structure. I think that must be it. Finally, definitely noctilucent clouds.

For more information about the how and why of all the phenomenon I've mentioned and many more, Les Cowley's Atmospheric Optics website is the best.

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