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Hello Karl and others,
Nice to hear about your observation. I got couple of nights ago nice
segment of
parhelic circle with 120° parhelia (or parselene) in a brief lunar
display...
In your display, I would say that the outher ring wasn't a 24° halo since
you
said that 9° halo was not bright. 24° halo and 9° halo goes hand in hand
and the
9° halo is usually much brighter than 24° halo.
In you display the outher ring was maybe 23° halo as you said. There is
several
observations and measured photographs of displays where 22° halo was not
present
with 9° halo. These displays usually are compined with faint 9° halo, 18°
parhelia (= lateral arcs), 18° halo, 23° halo and 23° upper parhelion.
This
18+23 companion is quite usual in odd radius dispays. In these cases 24°
halo
may be present, but it is usually impossible to separate it from 23° halo.
Usually 9° and 24° halos are with normal 22° halo (they all need hexagonal
prism
of ice crystal). Beside that, normal 22° halo usually overlay possible 24°
halo.
22° halo often overlay 23° halo too. So, even if they (23° and 24° halos)
are
present, they can be impossible to separate from 22° halo.
However, in many of odd radius displays you can't be sure what you saw
before
you carefully measure those radius from photos you took...
Best regars,
Jarmo Moilanen
Finnish Halo Observing Network
Dear members of the mailing-list,
at noon my family and I watched a marvelous halo phaenomenon at Schlägl.
Pyramidal crystals caused some rare halos: 23°-halo (almost complete),
both 18°
lateral arcs, complete 9° halo and the upper and lower 9° parhelions. All
figures were bright except the 9° halo. I am not sure if the outer ring
was the
23° halo, it could be the 24° halo too. I hope the pictures will show it
clearly.
The phaenomenon was visible in southern Germany too.
Regards
Karl
Karl Kaiser
http://home.eduhi.at/member/nature
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