Werner: an "X" on the Moon - this is a Clair-Obscur effect.
Clair-Obscur have no scientific importance and are just tricks of the
light that make us think we see something like a letter of the alphabet
or a shape or face. Clair-Obscur effects are scientifically pointless
to observe. However, if you want to be thrilled, or obtain an image to
impress someone then give them a go. If you do observe, or image this,
by all means send your observation into ALPO or the BAA, but we
probably won't publish, but will nevertheless retain in our archives,
just in case features elsewhere in the image are of interest to
future researchers.
These can only be observed using low-light level cameras running at 25 frames per sec,
or faster, and capable of recording 9th or 10th magnitude stars in real time.
Dates/UTs of observing runs, or detections of impacts, should be emailed to:
ALPO - email: c u d n i k @ s b c g l o b a l . n e t
BAA - email: a t c @ a b e r . a c . u k
UAI - email: a m . 5 4 8 5 2 @ g m a i l . c o m
BAA Request: Examine the floor visually, sketch, or image to
show the progression of the shadow spires across floor. If
observing visually, how would you describe the appearance of
the central lit area on the floor? If imaging, do a time lapse
e.g. 1 image per minute to show the progression of the shadow
spires. We are asking for these observations following an
observation by N. Travnok (Brazil) on 2020 Jul 27 UT 23:00 who
commented on an unusual appearance to the floor. It would be
really useful to have visual observing of the appearance and
please note down what the seeing conditions are like. If you
want to image it at high resolution, please go ahead but
remember that any image stacking should not be from sections
of video of longer than 1 min duration as the shadows change
in length rather quickly at sunrise. Any sketches, visual
descriptions, or images taken, should be emailed to:
a t c @ a b e r . a c. u k
BAA Request: It has been noticed that a bright carterlet can
appear very suddenly on the floor of Plato in between needle
like shadows, during local lunar sunrise. This happens in the
space of just a minute or so, and can look really quite dramatic.
This effect was first spotted by Brian Halls on 2014 Oct 31
Please send any high resolution images, detailed scetches, or
visual descriptions to: a t c @ a b e r . a c. u k .
BAA Request: Lassell - we are trying to compare a sketch made
by T.G. Elger (1883 Jan 13 UT 19:40), that appeared on the
front cover of the BAA's The Moon publication from 1956 Vol 5
No. 2, to what can be captured with modern day imagery. This
is a good way to compare and contrast observations made by eye
with CCD imagery.Telescopes of aperture 8", or larger, should
be used. Please send any images to:
a t c @ a b e r . a c. u k .
Plato's Hook: a hook like effect in one of the shadow spires in Plato,
near a rim - this is a Clair-Obscur effect. It was first seen by
H.P.Wilkins in 1952. Clair-Obscur have no scientific importance and
are just tricks of the light that make us think we see something
like a letter of the alphabet or a shape or face. Clair-Obscur
effects are scientifically pointless to observe. However, if you want
to be thrilled, or obtain an image to impress someone then give them
a go. If you do observe, or image this, by all means send your
observation into ALPO or the BAA, but we probably won't publish,
but will nevertheless retain in our archives, just in case
features elsewhere in the image are of interest to future
researchers.
BAA Request: How early can you see the central peak of this
crater illuminated by scattered light off the crater's west
illuminated rim? High resolution and/or long exposures needed
to capture detail inside the floor shadow. All images should
be sent to me on the email adrress below, whether or not you
were successful in capturing the central peak:
a t c @ a b e r . a c. u k
ALPO Request: On 2013 Apr 22 Paul Zellor noticed that the two
closely spaced NW dark bands in Aristarchus had some (non-blue)
color to them. Can we confirm his observation of natural colour
here? Ideally you should be using a telescope of 10" aperture, or
larger. Please send any high resolution color images, detailed
sketches, or visual descriptions to: a t c @ a b e r . a c. u k .
BAA Request: Any sign of colour on this crater? Exmaine it
through red and blue filters e.g. Wratten 28 and 44A. Also
would you say that the crater looks dull? We are especially
interested if you observe the cxrater under poor transparency
conditions. All observations, including visual descriptions,
sketches, or images should be emailed to:
a t c @ a b e r . a c. u k .
ALPO Request: Can you detect any colour, inside the crater, on
the floor and elsewhere? Can you image any colour? Minimum
telescope aperture needed: 6", and if possible try using a
refractor. All images or sketches should be sent
to me on this email adrress: a t c @ a b e r . a c. u k
BAA Request: Aristarchus area - We are trying to explain an
observation from Meudon Observatory in France made in 1881 of
a bright rope-like effect seen in the vicinity of this crater.
Please send any images to: a t c @ a b e r . a c. u k .
ALPO Request: Compare the crater in red and blue light - if
possible use Wratten 25 and Wratten 38A filters. If its
brighter in one filter than the other, is this because one
filter is a lot darker than the other, or is the effect
confined only to this crater? Any visual descriptions,
sketches, or colour images should be emailed to:
t o n y . c o o k @ a l p o - a s t r o n o m y . o r g
ALPO Request: Can you see a darkening on the northen floor of
this crater? All visual reports, sketches or color images should
be emailed to:
t o n y . c o o k @ a l p o - a s t r o n o m y . o r g
ALPO Request: Please supply images, or sketches, of this area,
especially covering the area to the east. Any size scope can be
used for this study. All observations should be emailed to:
a t c @ a b e r . a c. u k
BAA Request: Sketches or images needed of Toricelli B - of
sufficient resolution to reveal shadow. All observations,
including sketches or images shouild be emailed to:
a t c @ a b e r . a c. u k .
BAA Request: Cyrillus. There is a small white craterlet just
north of the three central peaks. We are interested to receive
high resolution images of this in order to find out at what
selenographic colongitude, in the lunar evening, that it loses
it's white spot appearence. Please use scopes largher than 6
inches in diameter.
Please email these to: a t c @ a b e r . a c . u k
These can only be observed using low-light level cameras running at 25 frames per sec,
or faster, and capable of recording 9th or 10th magnitude stars in real time.
Dates/UTs of observing runs, or detections of impacts, should be emailed to:
ALPO - email: c u d n i k @ s b c g l o b a l . n e t
BAA - email: a t c @ a b e r . a c . u k
UAI - email: a m . 5 4 8 5 2 @ g m a i l . c o m
These can only be observed using low-light level cameras running at 25 frames per sec,
or faster, and capable of recording 9th or 10th magnitude stars in real time.
Dates/UTs of observing runs, or detections of impacts, should be emailed to:
ALPO - email: c u d n i k @ s b c g l o b a l . n e t
BAA - email: a t c @ a b e r . a c . u k
UAI - email: a m . 5 4 8 5 2 @ g m a i l . c o m
These can only be observed using low-light level cameras running at 25 frames per sec,
or faster, and capable of recording 9th or 10th magnitude stars in real time.
Dates/UTs of observing runs, or detections of impacts, should be emailed to:
ALPO - email: c u d n i k @ s b c g l o b a l . n e t
BAA - email: a t c @ a b e r . a c . u k
UAI - email: a m . 5 4 8 5 2 @ g m a i l . c o m
These can only be observed using low-light level cameras running at 25 frames per sec,
or faster, and capable of recording 9th or 10th magnitude stars in real time.
Dates/UTs of observing runs, or detections of impacts, should be emailed to:
ALPO - email: c u d n i k @ s b c g l o b a l . n e t
BAA - email: a t c @ a b e r . a c . u k
UAI - email: a m . 5 4 8 5 2 @ g m a i l . c o m
These can only be observed using low-light level cameras running at 25 frames per sec,
or faster, and capable of recording 9th or 10th magnitude stars in real time.
Dates/UTs of observing runs, or detections of impacts, should be emailed to:
ALPO - email: c u d n i k @ s b c g l o b a l . n e t
BAA - email: a t c @ a b e r . a c . u k
UAI - email: a m . 5 4 8 5 2 @ g m a i l . c o m
ALPO Request: There is a bright spot on the NW shore of Mare
Crisium, which is normal. However please check its appearance
in a blue filter e.g. Wratten 38A. A minimum sized scope for
this task is 4" (ideally a refractor) with a magnification of
around x180. If taking colour imagery, please make sure that
the exposure is short enough so that the bright spot does not
saturate. All visual reports and colour images should be
emailed to:
t o n y . c o o k @ a l p o - a s t r o n o m y . o r g
These can only be observed using low-light level cameras running at 25 frames per sec,
or faster, and capable of recording 9th or 10th magnitude stars in real time.
Dates/UTs of observing runs, or detections of impacts, should be emailed to:
ALPO - email: c u d n i k @ s b c g l o b a l . n e t
BAA - email: a t c @ a b e r . a c . u k
UAI - email: a m . 5 4 8 5 2 @ g m a i l . c o m
These can only be observed using low-light level cameras running at 25 frames per sec,
or faster, and capable of recording 9th or 10th magnitude stars in real time.
Dates/UTs of observing runs, or detections of impacts, should be emailed to:
ALPO - email: c u d n i k @ s b c g l o b a l . n e t
BAA - email: a t c @ a b e r . a c . u k
UAI - email: a m . 5 4 8 5 2 @ g m a i l . c o m
These can only be observed using low-light level cameras running at 25 frames per sec,
or faster, and capable of recording 9th or 10th magnitude stars in real time.
Dates/UTs of observing runs, or detections of impacts, should be emailed to:
ALPO - email: c u d n i k @ s b c g l o b a l . n e t
BAA - email: a t c @ a b e r . a c . u k
UAI - email: a m . 5 4 8 5 2 @ g m a i l . c o m
Monte Caucasus: "shadow face" silhouette Clair-Obscur effect.
Clair-Obscur effects have no scientific importance just tricks
of the light that make us think we see something like
a letter of the alphabet or a shape or face. Clair-Obscur
effects are scientifically useless to observe. However, if
you want to be thrilled, or obtain an image to impress someone
then give them a go. This effect on the southern end of Montes
Caucuses looks like the side silhouette of a cartoon human face.
We are still slightly undertain about the precise colongitude
range, so if you do not see the face, try again later. If you
do observe, or image this, by all means send your observation
into ALPO or the BAA, but we probably won't publish, but will
nevertheless retain in our archives, just in case features
elsewhere in the image are of interest to future researchers.
Note that we have some uncertainty in the colongitude range
- so if you don't see it, please tells us the date and UT so
we can make some improvements in the predictions.
These can only be observed using low-light level cameras running at 25 frames per sec,
or faster, and capable of recording 9th or 10th magnitude stars in real time.
Dates/UTs of observing runs, or detections of impacts, should be emailed to:
ALPO - email: c u d n i k @ s b c g l o b a l . n e t
BAA - email: a t c @ a b e r . a c . u k
UAI - email: a m . 5 4 8 5 2 @ g m a i l . c o m
ALPO Request: Is there a dark patch surrounding this crater
tonight? We are just checking up on the normal appearance of
this crater and its surrounds, to verify an observational
report from 1994 during the ALPO Clementine watch. Use a
telescope of aperture 3.5 inches or larger. All sketches or
monochrome images should be emailed to:
t o n y . c o o k @ a l p o - a s t r o n o m y . o r g
These can only be observed using low-light level cameras running at 25 frames per sec,
or faster, and capable of recording 9th or 10th magnitude stars in real time.
Dates/UTs of observing runs, or detections of impacts, should be emailed to:
ALPO - email: c u d n i k @ s b c g l o b a l . n e t
BAA - email: a t c @ a b e r . a c . u k
UAI - email: a m . 5 4 8 5 2 @ g m a i l . c o m