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Some odd questions about optical phenomena in our atmosphere and
elsewhere.
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1/ About the Glory, the cloudbow, the sub-sun and the sub-parhelic circle.
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The Glory or "Brocken spectre", a set of diffuse multicolored rings
surrounding the observer's anti-solar point,
is a familiar sight to mountain dwellers and airplane travellers as long
as
their anti-solar point is projected on a
layer of fog or a moisty cloud-deck below.....
But is it also familiar for astronauts or cosmonauts orbiting the cloud
covered earth? In theory it must be possible
to observe ( parts of) the glory from a distance further out in space
whenever the observer's anti-solar point is projected
on the earth's cloud deck ( perhaps even from the moon?) and what about
the
cloud-bow, the sub-sun, the sub-parhelic
circle, sub-parhelia and the sub-anthelion?, could I find some photographs
of these optical phenomena, spotted from
earth-orbit?
Has anyone ever spotted a " mirror-glory", produced in the light of a low
sun reflected on the smooth surface of a lake?
( bear in mind that the sky on the opposite side of the Sun should be
cloud
covered !)
2/ About "Offset white arcs".
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Offset white arcs are colorless rainbows with not-so-normal postions in
the
sky: cloud it be that bright parhelia are the
cause of these white rainbows? ( I know, it must be a strange
meteorological situation: halo-effects on one side of the sky
and rainbow effects on the other).
3/ About Transient Lunar Phenomena.
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To anyone who owns a beaded projection screen: take it out and place it
the
sun, after you put on your sunglasses you will
see on the screen another aspect of "rainbow-dynamics": at about 22
degrees
( measured from the anti-solar point) you will
see the "primary glassy bead-bow": red on the outside an blue on the
inside
( the same as in the normal primary rainbow,
but the angular radius is relatively small), at about 87 degrees measured
from the anti-solar point you will find a very weak
and broad " secondary glassy bead-bow": blue on the sunward side and red
toward the anti-solar point ( note that this
measures a whole 87 degrees, almost 90 degree !).
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* WARNING !!!!!! Very bright, almost blinding retro-reflection when
beaded screen is placed face-on in the sun . *
* To reduce this glare, turn screen 60 degrees off-axis and the bow
will
become visible. *
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The point now is: is there a possibility that future lunar astronauts will
find huge concentrations of glassy beads and that
they will encounter some equivalent of the "primary beaded screen-bow"? (
the horizontal dewbow sometimes seen on
earth's early morning meadows), if this is possible we on earth must
sometimes see very little fragments of this
"primary lunar dust-bow" when the moon stands at about 22 degrees away
from
the ant-solar point ( a couple of days
before and (or) after full moon) , could this be the reason why lunar
observers claim they have seen reddish glows on the
moon from time to time? ( generally known as transient lunar
phenomena-tlp).
To all lovers of strange optical phenomena: I like to read your answers
and
observations and hope to develop with you
some new thechniques to discover " new" natural optical phenomena.......
by
the way, come and visit my " atmospherium"
in the city of Ghent, Belgium: a dome for astronomical purpose situated in
the " Popular observatory Armand Pien", the
inside of this dome is transformed into a painted all-sky representation
of
a huge halo-complex and bonus primary and
secondary rainbows!!! Unique !!!!
Luk Van Biesbrouck and Danny Caes
Best regards - Beste groetjes
Luk Van biesbrouck danny caes
St. Michielstraat 91
Krijgsgasthuisstraat 161
B-8700 Tielt Belgium B-9000
Gent
Belgium
Tel: +32.51.40.75.08 tel:
+32.9.223.98.03
E-mail : gi31113_at_glo.be
luk.vb_at_belgium-mail.com
URL : http://users.glo.be/vanbiesbrouck
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