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> At 03:55 I was about to open the shutter of the camera, and I saw
> `something diffuse' near zenith, i.e. north of Gemini. At a first
> glance it appeared like the moon shining through thick cirrus or so.
> (In fact, the moon was still below horizon.) I estimate the total
> brightness of the phenomenon as -1...-2 mag, while I was able to
> see stars up to +3/+4 with the naked eye. The object was elongated
> (about 1 deg wide, 6-7 deg long), showed no motion, and even in a
> 10x50 binocular there was no structure to be seen. I took a few
In 1988 a similar phenomenon was observed and photographed in
Rovaniemi, Finland. The case was published in local newspapers and
in "Tähdet ja Avaruus" 2/88. The case beared these qualities:
-elongated, relatively short, relatively bright spot
-near zenith
-white, no motion
-at most time no clear structure seen on binoculars,
in some photos a single knot in the core of the light
The spot was then linked to searchlight, a powerful artificial
light source making a stationary end spot in a narrow, invisible
layer of well-oriented ice crystals high in the air. When two big
searchlights were nearby turned on, then two small elongated spots
appeared close to zenith.
There were no other halo phenomena apparent in the sky, so the case
was at first hand a big mystery, and waked a lot of attention.
> photos between 04:02 MET and 04:14 MET. After 04:10 the brightness
> decreased remarkably, and (also due to thicker cirrus again) it
The cirrus might have turned to worse quality considering for
example well-oriented plates etc.
> disappeared after 04:15 MET. There was a little `knot-like' structure
> around 04:12 visible in the binocular.
In the Rovaniemi photos, at some stages a core of the light is discernable
- the brightest point of the reflection.
Its well imaginable that the cause of the spot could be something
else. Yet I tend to make a guess that when the Potsdam photos
are ready, they will look similar as the 1988 ones. In any case
I join Jurgen's and Jarmo's wishes - the more explanation alternatives
the more interesting (!).
It seems Veikko has just send a message, I wonder what he writes...
Regards, Marko Pekkola
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