Earlier in June I saw a couple of displays of noctilucent clouds (look at this previous post to find out what these clouds are and how they are formed). The first was on the night of 23rd/24th June when we were in Suffolk near Bawdsey and I initially saw them at 21:51 UT:-
I estimated that they reached a maximum elevation of about 18 degrees above the horizon and stretched from about azimuth 300 to azimuth 10 (azimuth 0 points due north and then increases eastwards along the horizon - so due east is 90 degrees, south 180 and west is 270). They were mostly in the form of bands (type 2) and waves (type 3).
I carried on seeing them for about 25 minutes (until 22:15 UT):-
By then the clouds had sunk lower to the horizon (just a maximum elevation of 12 degrees) and they stretched from azimuth 313 to 357 degrees. Both pictures were taken on a Samsung SM-A217F camera phone with an exposure of 1/10s, f/2.0, ISO 2000.
Five days later on the night of the 28th/29th June I observed another display from my home in Neatishead. Again, I caught sight of them at a starting time very similar to before (21:52 UT):-
You can see the NLC's as white wavy bands (type 3) behind the chimney pot of the house next door. Some foreground normal cloud is obscuring the view. I reckoned that the maximum elevation of the clouds stayed pretty much constant at 18 degrees above the horizon.
Eight minutes later at 22:00 UT the clouds appear brighter as the sky darkened:-
There appeared to be some brighter knots in the wavy clouds. At 22:12 UT the clouds appeared very bright and the structure was more complex:-
Also the clouds didn't appear to extend so far eastwards (although part of this may be due to obscuring foreground cloud). At 22:28 UT the clouds began to fade and I stopped observing:-
The camera and exposure settings were the same as above.
All text and images © Duncan Hale-Sutton 2024
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