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CaptainSandL
27th Jun 2003, 10:17
For those of you operating night flights this week and want something new to look at on the way home, try this:

For the last few nights I have been able to see a fairly rare phenomenon called noctilucent cloud, which I couldn’t find in my dusty old ATPL books but it did turn up in an internet search. You should look towards the day/night line after sunset and you may see some wispy white clouds even when it is dark enough to see the stars. They are apparently made of ice crystals and form at an altitude of 85km in the midsummer months near the polar regions but other than that we don’t know much about them.

I have put a photo of it at http://www.chris.brady.ukgateway.net/noctilucent.htm together with a link for more info from the boffins for those who are interested.

Has anybody else seen any other unusual or interesting sights at night? – Other than the usual UFO’s, Santa & reindeers and of course Elvis !

1000fps
27th Jun 2003, 16:03
In early evening just after sundown , whilst flying westbound in the Southern Ocean, a Shuttle flight orbited from Nw to Se.
It must have been pitched in the vertical plane with its tiled keel forward. Perhaps it was a lower orbit or just more ionospheric activity but the net result was a glow around the craft and a brilliant plume or rooster tail streaming miles above and aft.
It lasted a matter of minutes but was extraordinary.

moist
27th Jun 2003, 16:11
I once saw a crew meal at night, but sadly they have disappeared forever as well.

treadigraph
27th Jun 2003, 19:00
CaptainSandL,

Is this the same phenomenom known as After Glow? I know that's attributed to ultra high cloud catching light...

Article in the Telegraph on 26th June about Weather people seeing more types of electrical discharge out of the tops of CBs...

Cheers

Treadders

Smokie
27th Jun 2003, 19:21
Many moons ago I saw Appollo 17 on re-entry, pretty spectacular it was too .:cool:

NotFormallyKnown
27th Jun 2003, 20:46
Noctilucent Clouds are the joy of summer. Often missed by pilots, the same ones that see them blindly every summer, they are nevertheless there to be seen. Why not participate in observing them? You are not alone. There is a cordinated effort.

The "Noctilucent Cloud: Observers' Homepage" is where you should look. Their links are up to date, good and plentiful. Try:
__
http://www.nlcnet.co.uk

--------------Observing NLC is better then beer!



CaptainSandL,

No its not AfterGlow, not "Sprites" from CBs, not aurora, not rocket stuff. Simply seasonal polar clouds at about 50 miles. Too faint to see at day. Too north to see from south. Stuck in the bad weather or under populated region of high north (or far south in winter) where pilots have the BEST viewing oportunities. The viewing season is late May to early August so time is running out! Enjoy.

PAXboy
27th Jun 2003, 21:06
treadigraph: Is this the same phenomenom known as After Glow? No. After Glow results after much warmth, rather than ice crystals. However, if the operation is correctly executed, then crew (minimum of two) may feel that they are at the height of said Noctilucent Clouds, 80-85km (approx FL2800). :}

Loose rivets
28th Jun 2003, 07:28
I know this is going off the main point, but has anything further been discovered about Sprites. I wondered years ago if the entire CB might be LASEing. The core would be a very crude laser, but with the surfeit of power available and a tube of plasma/gasses who knows.

Globaliser
28th Jun 2003, 20:58
1000fps:
In early evening just after sundown , whilst flying westbound in the Southern Ocean, a Shuttle flight orbited from Nw to Se.
It must have been pitched in the vertical plane with its tiled keel forward. Perhaps it was a lower orbit or just more ionospheric activity but the net result was a glow around the craft and a brilliant plume or rooster tail streaming miles above and aft.
It lasted a matter of minutes but was extraordinary.Was it re-entering? Must have been magnificent.

ETOPS
29th Jun 2003, 01:50
Amazing coincidence but I was just pointing these type of clouds out to my co-pilot this morning. We were approaching 20W on track Y and as the dawn broke the clouds were very clearly visible - only the second time I've seen them....

javelin
29th Jun 2003, 21:36
Returning Eastbound on Wed night/Thur morning at about 6060N we had a double - Noctilucent clouds and Aurora together. All this with a pale blue glow over the pole - It made a poor chap feel very humble :ooh: