Noctilucent Clouds
- Thread starter HebburnMackem
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I
Icarebecauseyoudo
Guest
Not sure I believe this first appeared in 1885 stuff
First noted in 1885 more like. After all, if on the deck how do you distinguish them from cirrus and other high cloud?
First noted in 1885 more like. After all, if on the deck how do you distinguish them from cirrus and other high cloud?
HebburnMackem
Striker
Because at night they seem so self glow when all else is dark.
I
Icarebecauseyoudo
Guest
I suppose there is that
But only for 1 hour after sunset? In high summer there is always light in the sky in this country
HebburnMackem
Striker
The first time I noticed them was in 2009. I was a smoker at the time and had just come out of the pub for a tab, 11:20pm.
The photo is shit because I was drunk and only had a not-so-smart smartphone at the time.
The photo is shit because I was drunk and only had a not-so-smart smartphone at the time.
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I
Icarebecauseyoudo
Guest
Shot of the spire with them behind could have been a classic!
smoker
Striker
I suppose there is that
In high summer there is always light in the sky in this country
They tend to appear one hour after sunset and are visible all night till just before dawn.
http://www.flickr.com/photos/dangerous_astro/sets/72157622717720440/
There is no way you can possibly mistake them for Cirrus or general sky glow, the structure is far more intricate, they reflect the sun and they don't follow the prevailing low-level cloud patterns (eg - http://www.flickr.com/photos/dangerous_astro/3672408247/sizes/o/in/set-72157622717720440/)
I
Icarebecauseyoudo
Guest
Ok, so the assumption is they are a product of the industrial revolution?
smoker
Striker
They are caused by ice crystals forming around particles or vapour that have found their way into the mesosphere. So yes, more particulates means more NLCs. There's a possible link to global warming as those models predict mesospheric cooling. The suggestion that people simply didn't notice them doesn't hold water, astronomy wasn't invented in 1885.
I
Icarebecauseyoudo
Guest
anaar, it was 1992 when Sky Sky started
HebburnMackem
Striker
smoker
Striker
It's spooky cloud time of year.
Over Chopwel last night:
30D and old trusty Sigma 18-200.
Look north between midnight and 2am.
Townies should be able to get some nice shots over the harbour, you don't need dark skies to see these, just insomnia.
Over Chopwel last night:
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30D and old trusty Sigma 18-200.
Look north between midnight and 2am.
Townies should be able to get some nice shots over the harbour, you don't need dark skies to see these, just insomnia.
I
Icarebecauseyoudo
Guest
See anyone wearing a badger or fox mask?
smoker
Striker
I
Icarebecauseyoudo
Guest
Is that how you do dogging in Yorkshire?
Essex apparently
What exposure stats?
They are very sharp
smoker
Striker
Essex apparently
What exposure stats?
They are very sharp
IIRC 5 or 6 seconds, ISO800, f7 or f8, infinity focus.
Sharpened up in Tattyshop, the 18-200 is a bit soft at longer focal lengths.
I
Icarebecauseyoudo
Guest
Ok, nice, assumed a bigger iso or aperture than that, must be very bright!
smoker
Striker
Much brighter than aurora - I'd usually be looking at 20-30 secs, ISO1600/f2.8 from a dark sky site for that.
HebburnMackem
Striker
It's the tail end of The Nexus, which is an extradimensional realm in which one's thoughts and desires shape reality. Inside the Nexus, time has no meaning, allowing one to visit any time and any place that one can imagine.
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I
Icarebecauseyoudo
Guest
Shame there was none of that light when you were taking that fat bloke's photo
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