Moonshadows: angle makes no sense.

Mike Williams wrote:
I've managed to reproduce the effect in a 3D imaging program, POV-Ray,
but only when the Moon is slightly gibbous. When it's exactly first
quarter the illumination is as you'd expect it.

POV-Ray is a well established program that has been used by huge numbers
of people who complain bitterly on the associated newsgroups about its
slightest flaw, and they've never mentioned problems with illumination
directions. So I consider it trustworthy ion this respect.

Here's a still image of the Moon, illuminated by a Sun that's out of
frame on the horizon.
http://www.econym.demon.co.uk/temp/moon.jpg

And here's an animation panning round from the Moon to the Sun.
http://www.econym.demon.co.uk/temp/moon.gif


Wonderful graphics but nobody around who is good enough to seperate
axial rotation from orbital motion to capture the full effect.

The price for the celestial sphere peep show, by using the axial and
orbital motions of the Earth improperly, is that simple astronomical
affirmations by viewing the Earth from space cannot be used.

In that animation I see axial rotation while leaving the effect of
orbital orientation on its own terms while you have your very
geocentric 'sunset' and a variable tilting Earth -

http://www.scienceu.com/observatory/...s/seasons.html

With neither sense nor authority to do what is so easy for me,you waste
those wonderful graphics in order to save your dumb Ra/Dec conventions.



I've added one cylindrical ray from the Sun to the moon. It looks fatter
at the Moon end because that end is about 372 times closer to the
camera. All frames are conventional perspective views.

The light ray is a perfectly straight line in each individual frame, but
the angle of the line varies from frame to frame.

You can imagine how the effect works if you consider a pair of parallel
lines that stretch from horizon to horizon and pass just North of the
point where you're standing. When you look West, the lines appear to be
straight lines that converge at a point on the western horizon. When you
look East, the lines appear to be straight lines that converge at a
point on the eastern horizon. When you look North they appear to be
straight parallel lines. Whichever direction you look, or take a
photograph, the lines are perfectly straight in each individual image,
but as you turn your head or camera, the angle between those straight
lines changes.

My killfile appears to have eaten 10 of the postings in this thread, so
I apologise if any of this duplicates what's been said in the posts that
I've not read.

--
Mike Williams
Gentleman of Leisure

"Mark McIntyre" wrote in message
...

appropriate apology to Gerald snipped to save even more embarrassment

Mark McIntyre ( ) )

Yes - and not only that, but you're not even good enough to 'seperate' axial
rotation from orbital motion to capture the full effect. What you have
missed entirely is that in the case of Kepplerian astrologer trolls, 'their
path does _not_ appear straight'. Your ardent belief that the moon is made
of green cheese and that the sun is a mere flashlight powered by 4 Duracells
just shows what kind of contemptible ******* you are. I rest my case and
only wonder who the men in white coats will seize upon first.

Picard's prosthetic heart is later replaced twice: in 2365 because of
defects in the originally installed model ("Samaritan Snare"); and in 2369
because of damage sustained when Picard is shot in the chest point-blank
with a Lenarian compressed tetryon beam weapon runs him through like a
smoked sausage. Ah - one of Blair's planned walk-in heart clinics in
action!

There are far too many people just like you insofar as having nothing
productive to say and with little grasp of what is astronomically
occuring,all that is left is to make yourselves feel important by
whatever miserable means you think necessary.Newton was really the
first to speak of the 'vulgar' while being particularly pretensious
himself-

"Hitherto I have laid down the definitions of such words as are less
known, and explained the sense in which I would have them to be
understood in the following discourse. I do not define time, space,
place and motion, as being well known to all. Only I must observe, that
the vulgar conceive those quantities under no other notions but from
the relation they bear to sensible objects. And thence arise certain
prejudices, for the removing of which, it will be convenient to
distinguish them into absolute and relative, true and apparent,
mathematical and common."

You would hardly have the neccesary aptitude to recognise the awful
manipulation that was about to occur when that guy set about creating
concepts based on the celestial sphere Ra/Dec system but I assure you
'vulgar' is far too mild an expression for the awful creation which is
still dominant.

I will say that the sheer incapacity to work with motions and
orientations locally displays that there is no appreciation of the
sheer power and size of our central star or the huge scale of orbital
geometries leads to these silly and tepid ways to look on on celestial
phenomena.The graphics would be excellent if they promoted a sense of
what is moving and what is not along with the size and powerr of the
Sun but they do not.What can be said of people who have images of the
Earth from space and still cannot adapt but unfortunately withoput
sense or authority your only avenue is to mutter some stupid comments
at me.

Keep on commenting on this excellent subject for it is a step into
appreciating the change in orbital orientation against fixed axial
orientation which in turn leads to the sprawling topic of climate.So
far, using the Sun like a flashlight to explain hemispherical weather
patterns (seasons) is every bit as pathetic as using the flashlight
principle to explain the moon's appearance.Get used to not referencing
local objects to our distant central star and allow the Earth and the
moon to move in direct solar radiation.









TeaTime wrote:
"Mark McIntyre" wrote in message
...

appropriate apology to Gerald snipped to save even more embarrassment

Mark McIntyre ( ) )

Yes - and not only that, but you're not even good enough to 'seperate' axial
rotation from orbital motion to capture the full effect. What you have
missed entirely is that in the case of Kepplerian astrologer trolls, 'their
path does _not_ appear straight'. Your ardent belief that the moon is made
of green cheese and that the sun is a mere flashlight powered by 4 Duracells
just shows what kind of contemptible ******* you are. I rest my case and
only wonder who the men in white coats will seize upon first.

Picard's prosthetic heart is later replaced twice: in 2365 because of
defects in the originally installed model ("Samaritan Snare"); and in 2369
because of damage sustained when Picard is shot in the chest point-blank
with a Lenarian compressed tetryon beam weapon runs him through like a
smoked sausage. Ah - one of Blair's planned walk-in heart clinics in
action!

Mike Williams wrote:
I've managed to reproduce the effect in a 3D imaging program, POV-Ray,
but only when the Moon is slightly gibbous. When it's exactly first
quarter the illumination is as you'd expect it.

POV-Ray is a well established program that has been used by huge numbers
of people who complain bitterly on the associated newsgroups about its
slightest flaw, and they've never mentioned problems with illumination
directions. So I consider it trustworthy ion this respect.

Here's a still image of the Moon, illuminated by a Sun that's out of
frame on the horizon.
http://www.econym.demon.co.uk/temp/moon.jpg

And here's an animation panning round from the Moon to the Sun.
http://www.econym.demon.co.uk/temp/moon.gif

I've added one cylindrical ray from the Sun to the moon. It looks fatter
at the Moon end because that end is about 372 times closer to the
camera. All frames are conventional perspective views.

The light ray is a perfectly straight line in each individual frame, but
the angle of the line varies from frame to frame.

You can imagine how the effect works if you consider a pair of parallel
lines that stretch from horizon to horizon and pass just North of the
point where you're standing. When you look West, the lines appear to be
straight lines that converge at a point on the western horizon. When you
look East, the lines appear to be straight lines that converge at a
point on the eastern horizon. When you look North they appear to be
straight parallel lines. Whichever direction you look, or take a
photograph, the lines are perfectly straight in each individual image,
but as you turn your head or camera, the angle between those straight
lines changes.

My killfile appears to have eaten 10 of the postings in this thread, so
I apologise if any of this duplicates what's been said in the posts that
I've not read.

--
Mike Williams
Gentleman of Leisure

http://www.econym.demon.co.uk/temp/moon.gif

To get the right perspective,you ignore axial rotation and consider
radiation striking the moon from the point of view of the Earth's
orbital motion .This means dropping the geocentric 'arc of the Sun'
above and below the horizon ,not just for this topic but for the
correct way to understand cyclical variations in daylight/darkness and
subsequerntly hemispherical weather patterns (seasons)

The sprawling area of climate depends on getting this right and so far
I have not seen one competent response.Even though the graphics are
excellent and a spectacular way to answer the question,unfortunately
you still insist in referencing local objects to the distant Sun rather
than treating motions locally and using solar radiation as a backdrop
to the change in motions and subsequently orientations to direct
radiation..

The price of a variable tilting Earth to the Sun to explain the seasons
is now so untenable and ultimately so counter-productive that there
appears to be very little hope for a proper understanding of global
climate and the cyclical motions of the Earth in solar radiation which
makes existence possible.

Of course you need your celestial sphere peep show and who would
disturb those who make a living calling themselves 'astronomers' by
virtue of magnification alone.